World's Best Scientists 2026 revealed!
VIEW LIST
Mohammad Hossein Enayati

Mohammad Hossein Enayati

Isfahan University of Technology
Iran

D-Index & Metrics

Discipline name D-Index World Ranking Current World Ranking National Ranking Current National Ranking Publications Citations
Materials Science 45 11859 11465 67 67 205 6188

Mohammad Hossein Enayati publications per year

The chart shows the history of publications by Mohammad Hossein Enayati between 1996 and 2021, highlighting the no. of papers published in each year and offering an overview of the publication velocity of this scholar. Mohammad Hossein Enayati published across 26 years, from 1996 to 2021, averaging 7.9 papers a year. Output peaked at 20 publications in 2009. 20 of the 205 publications appeared in the last two years.

No. of publications
5 10 15 20
Bar chart. Horizontal axis: year, 1996 to 2021. Vertical axis: number of publications, 0 to 20. Peak 20 publications in 2009. 1996: 1 publication 1997: 0 publications 1998: 0 publications 1999: 1 publication 2000: 0 publications 2001: 0 publications 2002: 1 publication 2003: 1 publication 2004: 4 publications 2005: 2 publications 2006: 1 publication 2007: 3 publications 2008: 11 publications 2009: 20 publications 2010: 16 publications 2011: 14 publications 2012: 20 publications 2013: 17 publications 2014: 15 publications 2015: 14 publications 2016: 14 publications 2017: 15 publications 2018: 5 publications 2019: 10 publications 2020: 7 publications 2021: 13 publications
1996 2021

205 publications in total across all disciplines

View publications per year as a table
Mohammad Hossein Enayati: publications per year, 1996 to 2021
Year Publications
1996 1
1997 0
1998 0
1999 1
2000 0
2001 0
2002 1
2003 1
2004 4
2005 2
2006 1
2007 3
2008 11
2009 20
2010 16
2011 14
2012 20
2013 17
2014 15
2015 14
2016 14
2017 15
2018 5
2019 10
2020 7
2021 13
Total 205
Download as CSV

Mohammad Hossein Enayati publication distribution in Materials Science in 2026

The chart shows the distribution of publications by all Research.com ranked scientists in the field of Materials Science in 2026. The highlighted bar marks where Mohammad Hossein Enayati sits on this spectrum.

No. of scientists
200 400 600 800
Bar chart with 57 bars. Horizontal axis: publications, 50–69 to 1,163+. Vertical axis: number of scientists, 0 to 891. Most scientists, 891, have 190–209 publications. The last bar groups every scientist with 1,163 publications or more. The highlighted bar, 190–209 publications, is where this scientist sits. 50–69 publications: 28 scientists 70–89 publications: 152 scientists 90–109 publications: 356 scientists 110–129 publications: 487 scientists 130–149 publications: 723 scientists 150–169 publications: 835 scientists 170–189 publications: 850 scientists 190–209 publications: 891 scientists 210–229 publications: 862 scientists 230–249 publications: 766 scientists 250–269 publications: 726 scientists 270–289 publications: 665 scientists 290–309 publications: 593 scientists 310–329 publications: 537 scientists 330–349 publications: 477 scientists 350–369 publications: 440 scientists 370–389 publications: 356 scientists 390–409 publications: 321 scientists 410–429 publications: 256 scientists 430–449 publications: 246 scientists 450–469 publications: 216 scientists 470–489 publications: 212 scientists 490–509 publications: 174 scientists 510–529 publications: 194 scientists 530–549 publications: 162 scientists 550–569 publications: 131 scientists 570–589 publications: 111 scientists 590–609 publications: 103 scientists 610–629 publications: 99 scientists 630–649 publications: 77 scientists 650–669 publications: 92 scientists 670–689 publications: 56 scientists 690–709 publications: 53 scientists 710–729 publications: 53 scientists 730–749 publications: 38 scientists 750–769 publications: 52 scientists 770–789 publications: 43 scientists 790–809 publications: 38 scientists 810–829 publications: 34 scientists 830–849 publications: 25 scientists 850–869 publications: 18 scientists 870–889 publications: 20 scientists 890–909 publications: 24 scientists 910–929 publications: 27 scientists 930–949 publications: 20 scientists 950–969 publications: 17 scientists 970–989 publications: 10 scientists 990–1,009 publications: 16 scientists 1,010–1,029 publications: 13 scientists 1,030–1,049 publications: 12 scientists 1,050–1,069 publications: 9 scientists 1,070–1,089 publications: 8 scientists 1,090–1,109 publications: 7 scientists 1,110–1,129 publications: 9 scientists 1,130–1,149 publications: 2 scientists 1,150–1,162 publications: 5 scientists 1,163+ publications: 100 scientists
50–69 publications 1,163+

This scientist: 205 publications — 32nd percentile

32% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 1,163 publications or more.

View publications distribution as a table
Number of Materials Science scientists by publication count, Research.com 2026 ranking edition. Based on 12,847 ranked scientists.
Publications Scientists This scientist
50–69 28
70–89 152
90–109 356
110–129 487
130–149 723
150–169 835
170–189 850
190–209 891 205
210–229 862
230–249 766
250–269 726
270–289 665
290–309 593
310–329 537
330–349 477
350–369 440
370–389 356
390–409 321
410–429 256
430–449 246
450–469 216
470–489 212
490–509 174
510–529 194
530–549 162
550–569 131
570–589 111
590–609 103
610–629 99
630–649 77
650–669 92
670–689 56
690–709 53
710–729 53
730–749 38
750–769 52
770–789 43
790–809 38
810–829 34
830–849 25
850–869 18
870–889 20
890–909 24
910–929 27
930–949 20
950–969 17
970–989 10
990–1,009 16
1,010–1,029 13
1,030–1,049 12
1,050–1,069 9
1,070–1,089 8
1,090–1,109 7
1,110–1,129 9
1,130–1,149 2
1,150–1,162 5
1,163+ 100
Download as CSV

Mohammad Hossein Enayati D-index placement in Materials Science in 2026

The chart shows the D-index (discipline H-index) distribution of Materials Science scientists ranked by Research.com in 2026. The highlighted bar marks where Mohammad Hossein Enayati sits on this spectrum.

No. of scientists
200 400 600
Bar chart with 64 bars. Horizontal axis: D-Index, 40–41 to 165+. Vertical axis: number of scientists, 0 to 667. Most scientists, 667, have 52–53 D-Index. The last bar groups every scientist with 165 D-Index or more. The highlighted bar, 44–45 D-Index, is where this scientist sits. 40–41 D-Index: 211 scientists 42–43 D-Index: 450 scientists 44–45 D-Index: 612 scientists 46–47 D-Index: 612 scientists 48–49 D-Index: 598 scientists 50–51 D-Index: 657 scientists 52–53 D-Index: 667 scientists 54–55 D-Index: 621 scientists 56–57 D-Index: 597 scientists 58–59 D-Index: 610 scientists 60–61 D-Index: 587 scientists 62–63 D-Index: 606 scientists 64–65 D-Index: 533 scientists 66–67 D-Index: 490 scientists 68–69 D-Index: 469 scientists 70–71 D-Index: 378 scientists 72–73 D-Index: 421 scientists 74–75 D-Index: 359 scientists 76–77 D-Index: 323 scientists 78–79 D-Index: 299 scientists 80–81 D-Index: 230 scientists 82–83 D-Index: 210 scientists 84–85 D-Index: 195 scientists 86–87 D-Index: 203 scientists 88–89 D-Index: 175 scientists 90–91 D-Index: 175 scientists 92–93 D-Index: 142 scientists 94–95 D-Index: 121 scientists 96–97 D-Index: 117 scientists 98–99 D-Index: 107 scientists 100–101 D-Index: 88 scientists 102–103 D-Index: 85 scientists 104–105 D-Index: 68 scientists 106–107 D-Index: 62 scientists 108–109 D-Index: 57 scientists 110–111 D-Index: 45 scientists 112–113 D-Index: 49 scientists 114–115 D-Index: 50 scientists 116–117 D-Index: 34 scientists 118–119 D-Index: 38 scientists 120–121 D-Index: 37 scientists 122–123 D-Index: 29 scientists 124–125 D-Index: 28 scientists 126–127 D-Index: 24 scientists 128–129 D-Index: 33 scientists 130–131 D-Index: 28 scientists 132–133 D-Index: 21 scientists 134–135 D-Index: 20 scientists 136–137 D-Index: 23 scientists 138–139 D-Index: 17 scientists 140–141 D-Index: 12 scientists 142–143 D-Index: 17 scientists 144–145 D-Index: 21 scientists 146–147 D-Index: 13 scientists 148–149 D-Index: 11 scientists 150–151 D-Index: 14 scientists 152–153 D-Index: 13 scientists 154–155 D-Index: 9 scientists 156–157 D-Index: 10 scientists 158–159 D-Index: 7 scientists 160–161 D-Index: 4 scientists 162–163 D-Index: 4 scientists 164 D-Index: 3 scientists 165+ D-Index: 98 scientists
40–41 D-Index 165+

This scientist: 45 D-Index — 10th percentile

10% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 165 D-Index or more.

View D-Index distribution as a table
Number of Materials Science scientists by D-index, Research.com 2026 ranking edition. Based on 12,847 ranked scientists.
D-Index Scientists This scientist
40–41 211
42–43 450
44–45 612 45
46–47 612
48–49 598
50–51 657
52–53 667
54–55 621
56–57 597
58–59 610
60–61 587
62–63 606
64–65 533
66–67 490
68–69 469
70–71 378
72–73 421
74–75 359
76–77 323
78–79 299
80–81 230
82–83 210
84–85 195
86–87 203
88–89 175
90–91 175
92–93 142
94–95 121
96–97 117
98–99 107
100–101 88
102–103 85
104–105 68
106–107 62
108–109 57
110–111 45
112–113 49
114–115 50
116–117 34
118–119 38
120–121 37
122–123 29
124–125 28
126–127 24
128–129 33
130–131 28
132–133 21
134–135 20
136–137 23
138–139 17
140–141 12
142–143 17
144–145 21
146–147 13
148–149 11
150–151 14
152–153 13
154–155 9
156–157 10
158–159 7
160–161 4
162–163 4
164 3
165+ 98
Download as CSV

Best Publications

  • Fabrication and evaluation of mechanical and tribological properties of boron carbide reinforced aluminum matrix nanocomposites

    E. Mohammad Sharifi;F. Karimzadeh;M.H. Enayati

  • A novel approach for development of surface nanocomposite by friction stir processing

    B. Zahmatkesh;M.H. Enayati

  • A novel technique for development of A356/Al2O3 surface nanocomposite by friction stir processing

    Y. Mazaheri;F. Karimzadeh;M.H. Enayati

  • Application of mechanical alloying/milling for synthesis of nanocrystalline and amorphous materials

    M. H. Enayati;F. A. Mohamed

  • The effect of milling parameters on the synthesis of Ni3Al intermetallic compound by mechanical alloying

    M.H. Enayati;Z. Sadeghian;M. Salehi;A. Saidi

  • Tribological and microstructural evaluation of friction stir processed Al2024 alloy

    B. Zahmatkesh;M.H. Enayati;F. Karimzadeh

  • Tribological properties of Al6061–Al2O3 nanocomposite prepared by milling and hot pressing

    N. Hosseini;F. Karimzadeh;M.H. Abbasi;M.H. Enayati

  • Production of nanostructured WC–Co powder by ball milling

    M.H. Enayati;G.R. Aryanpour;A. Ebnonnasir

  • Microstructural and mechanical evaluation of Al-TiB2 nanostructured composite fabricated by mechanical alloying

    Z. Sadeghian;B. Lotfi;M.H. Enayati;P. Beiss

  • Mechanical properties of nanostructured Al2024-MWCNT composite prepared by optimized mechanical milling and hot pressing methods

    M. Jafari;M.H. Abbasi;M.H. Enayati;F. Karimzadeh

  • Synthesis of nanocrystalline NiAl by mechanical alloying

    M.H. Enayati;F. Karimzadeh;S.Z. Anvari

  • Formation mechanism of Fe3Al and FeAl intermetallic compounds during mechanical alloying

    M. H. Enayati;M. Salehi

  • Fabrication of Al–Zn/α-Al2O3 nanocomposite by mechanical alloying

    M. Tavoosi;F. Karimzadeh;M.H. Enayati

  • Synthesis and characterization of NiAl–Al2O3 nanocomposite powder by mechanical alloying

    S.Z. Anvari;F. Karimzadeh;M.H. Enayati

  • Synthesis of nanocrystalline MoSi2 by mechanical alloying

    M. Zakeri;R. Yazdani-Rad;M.H. Enayati;M.R. Rahimipour

  • Wear characteristics of Al–Cr–O surface nano-composite layer fabricated on Al6061 plate by friction stir processing

    S.R. Anvari;F. Karimzadeh;M.H. Enayati

  • EFFECT OF COMPOSITION ON STRUCTURAL AND MAGNETIC PROPERTIES OF NANOCRYSTALLINE BALL MILLED NI1-XZNXFE2O4 FERRITE

    M. Jalaly;M.H. Enayati;P. Kameli;F. Karimzadeh

  • Bulk Al–Zn/Al2O3 nanocomposite prepared by reactive milling and hot pressing methods

    M. Tavoosi;F. Karimzadeh;M.H. Enayati;A. Heidarpour

  • The role of martensitic transformation on bimodal grain structure in ultrafine grained AISI 304L stainless steel

    S. Sabooni;F. Karimzadeh;M.H. Enayati;A.H.W. Ngan

  • Microstructural and mechanical characterizations of a novel HVOF-sprayed WC-Co coating deposited from electroless Ni–P coated WC-12Co powders

    M. Jafari;M.H. Enayati;M. Salehi;S.M. Nahvi

  • Study on solid-state reactions of nanocrystalline TiAl synthesized by mechanical alloying

    N. Forouzanmehr;F. Karimzadeh;M.H. Enayati

Frequent Co-Authors

Fathallah Karimzadeh
Fathallah Karimzadeh Isfahan University of Technology
Morteza Shamanian
Morteza Shamanian Isfahan University of Technology
Brian Cantor
Brian Cantor University of Oxford
Keyvan Raeissi
Keyvan Raeissi Isfahan University of Technology
A.H.W. Ngan
A.H.W. Ngan University of Hong Kong
Mohammadhossein Fathi
Mohammadhossein Fathi Isfahan University of Technology
Sun Ig Hong
Sun Ig Hong Chungnam National University
Hyoung Seop Kim
Hyoung Seop Kim Pohang University of Science and Technology
Nigel Sammes
Nigel Sammes Pohang University of Science and Technology
Rasoul Esmaeely Neisiany
Rasoul Esmaeely Neisiany Silesian University of Technology

External Links

Personal website of Mohammad Hossein Enayati

If you think any of the details on this page are incorrect, let us know.

Report an issue

We appreciate your kind effort to assist us to improve this page, it would be helpful providing us with as much detail as possible in the text box below:

Best Scientists Citing Mohammad Hossein Enayati

Fathallah Karimzadeh

Fathallah Karimzadeh

Isfahan University of Technology

Publications: 34

Morteza Shamanian

Morteza Shamanian

Isfahan University of Technology

Publications: 25

Yifu Shen

Yifu Shen

Nanjing University of Aeronautics and Astronautics

Publications: 21

Hamed Mirzadeh

Hamed Mirzadeh

University of Tehran

Publications: 16

Isaac Dinaharan

Isaac Dinaharan

University of Johannesburg

Publications: 16

B.S. Murty

B.S. Murty

Indian Institute of Technology Hyderabad

Publications: 12

Dongdong Gu

Dongdong Gu

Nanjing University of Aeronautics and Astronautics

Publications: 11

Adrian P. Gerlich

Adrian P. Gerlich

University of Waterloo

Publications: 11

Amir Hossein Kokabi

Amir Hossein Kokabi

Sharif University of Technology

Publications: 10

Arshad Noor Siddiquee

Arshad Noor Siddiquee

Jamia Millia Islamia

Publications: 10

Pasquale Cavaliere

Pasquale Cavaliere

University of Salento

Publications: 10

Hyoung Seop Kim

Hyoung Seop Kim

Pohang University of Science and Technology

Publications: 9

Seeram Ramakrishna

Seeram Ramakrishna

Tsinghua University

Publications: 9

Manoj Gupta

Manoj Gupta

National University of Singapore

Publications: 8

Xuanhui Qu

Xuanhui Qu

University of Science and Technology Beijing

Publications: 7

C. Suryanarayana

C. Suryanarayana

City University of Hong Kong

Publications: 7

Trending Scientists

Katsuhiko Ariga

Katsuhiko Ariga

National Institute for Materials Science

Oleg Gang

Oleg Gang

Columbia University

Alberto Vilagrosa

Alberto Vilagrosa

University of Alicante

Sandra H. Losoya

Sandra H. Losoya

Arizona State University

Gerald J. Fishman

Gerald J. Fishman

Marshall Space Flight Center

Steven L. Small

Steven L. Small

The University of Texas at Dallas

Durelle T. Scott

Durelle T. Scott

Virginia Tech

Eric Lichtfouse

Eric Lichtfouse

Aix-Marseille University

Gert Fricker

Gert Fricker

Heidelberg University

Anne Spang

Anne Spang

University of Basel

Yann Guiguen

Yann Guiguen

INRAE : Institut national de recherche pour l'agriculture, l'alimentation et l'environnement

Lars-Erik Åmand

Lars-Erik Åmand

Chalmers University of Technology

Martin Karafiat

Martin Karafiat

Brno University of Technology

Michael Hanfland

Michael Hanfland

European Synchrotron Radiation Facility

Anne Lesage

Anne Lesage

École Normale Supérieure de Lyon

Jason B. Fleming

Jason B. Fleming

The University of Texas MD Anderson Cancer Center

Related Materials Science Rankings & Guides

2027 How to Become a Nurse Practitioner in New Jersey

2027 How to Become a Nurse Practitioner in New Jersey
2027 What Is the Average Salary Outlook with MPH Degree?

2027 What Is the Average Salary Outlook with MPH Degree?
Most Affordable Diagnostic Medical Sonographer Schools & Training - Budget-Friendly Sonography Trade Programs in California for 2026

Most Affordable Diagnostic Medical Sonographer Schools & Training - Budget-Friendly Sonography Trade Programs in California for 2026
Most Affordable Pharmacy Technician Schools & Training - Budget-Friendly Pharmacy Tech Trade Programs in Minnesota for 2026

Most Affordable Pharmacy Technician Schools & Training - Budget-Friendly Pharmacy Tech Trade Programs in Minnesota for 2026
Most Affordable Diagnostic Medical Sonographer Schools & Training - Budget-Friendly Sonography Trade Programs in South Carolina for 2026

Most Affordable Diagnostic Medical Sonographer Schools & Training - Budget-Friendly Sonography Trade Programs in South Carolina for 2026
Most Affordable Diagnostic Medical Sonographer Schools & Training - Budget-Friendly Sonography Trade Programs in Florida for 2026

Most Affordable Diagnostic Medical Sonographer Schools & Training - Budget-Friendly Sonography Trade Programs in Florida for 2026
2027 Medical Jobs That Don't Require a College Degree

2027 Medical Jobs That Don't Require a College Degree
2027 How to Become a Nutritionist in Colorado

2027 How to Become a Nutritionist in Colorado
2027 What Does a DNP Do? Roles & Responsibilities

2027 What Does a DNP Do? Roles & Responsibilities
2027 How to Become a Nutritionist in Alaska

2027 How to Become a Nutritionist in Alaska
September 2027 Nurse Practitioner Careers: Guide to Career Paths, Options & Salary

September 2027 Nurse Practitioner Careers: Guide to Career Paths, Options & Salary
2027 What is a Medical Administrative Assistant? Job Description & Career

2027 What is a Medical Administrative Assistant? Job Description & Career
2027 What Can You Do With a Public Health MSN Degree?

2027 What Can You Do With a Public Health MSN Degree?
Most Affordable Pharmacy Technician Schools & Training - Budget-Friendly Pharmacy Tech Trade Programs in Fremont for 2026

Most Affordable Pharmacy Technician Schools & Training - Budget-Friendly Pharmacy Tech Trade Programs in Fremont for 2026
Best Pharmacy Technician Training Programs & Trade Schools - Top Pharmacy Tech Schools in New Jersey for 2026

Best Pharmacy Technician Training Programs & Trade Schools - Top Pharmacy Tech Schools in New Jersey for 2026
2026 Best Public Health Degree Programs Ranking in the USA

2026 Best Public Health Degree Programs Ranking in the USA
2027 Best Nursing Schools in Atlanta, GA – Accredited Nursing Degree Programs Online

2027 Best Nursing Schools in Atlanta, GA – Accredited Nursing Degree Programs Online
2027 Online Ultrasound Tech Schools

2027 Online Ultrasound Tech Schools
Most Affordable Physical Therapist Assistant Schools & Training - Budget-Friendly PTA Trade Programs in Florida for 2026

Most Affordable Physical Therapist Assistant Schools & Training - Budget-Friendly PTA Trade Programs in Florida for 2026
2027 How to Become a Nurse Informaticist: Salary & Career Paths

2027 How to Become a Nurse Informaticist: Salary & Career Paths
Most Affordable Pharmacy Technician Schools & Training - Budget-Friendly Pharmacy Tech Trade Programs in Michigan for 2026

Most Affordable Pharmacy Technician Schools & Training - Budget-Friendly Pharmacy Tech Trade Programs in Michigan for 2026

Recently Published Articles

2027 Different Types of Marriage and Family Therapy Degrees and Their Salaries

2027 Different Types of Marriage and Family Therapy Degrees and Their Salaries
2027 How to Become a Licensed Counselor (LPC) in Wisconsin

2027 How to Become a Licensed Counselor (LPC) in Wisconsin
2027 What Can You Do with a Social Media Master's Degree? Careers, Salaries & Growth

2027 What Can You Do with a Social Media Master's Degree? Careers, Salaries & Growth
2027 Competency-Based Online Speech Pathology Master's Degrees

2027 Competency-Based Online Speech Pathology Master's Degrees
2027 How Many Credits Can You Transfer Into a Physical Therapy Assistant Degree Program?

2027 How Many Credits Can You Transfer Into a Physical Therapy Assistant Degree Program?
2027 Best Nursing Schools in New Jersey – Accredited ADN, BSN, MSN Programs

2027 Best Nursing Schools in New Jersey – Accredited ADN, BSN, MSN Programs
2027 Last-Minute Admissions: Online Biology Degree Master's Programs Still Accepting Students

2027 Last-Minute Admissions: Online Biology Degree Master's Programs Still Accepting Students
2027 Can You Complete an Online Biology Degree Program While Working Full-Time?

2027 Can You Complete an Online Biology Degree Program While Working Full-Time?
2027 AI Master's Degrees for HR Professionals

2027 AI Master's Degrees for HR Professionals
2027 Associate to Bachelor's in Game Programming & Development: Transfer Pathways Explained

2027 Associate to Bachelor's in Game Programming & Development: Transfer Pathways Explained
2027 Most Flexible Careers You Can Pursue With a Health Sciences Degree: Remote, Hybrid, and Freelance Paths

2027 Most Flexible Careers You Can Pursue With a Health Sciences Degree: Remote, Hybrid, and Freelance Paths
2027 Easiest and Hardest Science Majors

2027 Easiest and Hardest Science Majors
2027 Best ABSN Programs - List of Accelerated BSN Programs in Minnesota: Online & Campus

2027 Best ABSN Programs - List of Accelerated BSN Programs in Minnesota: Online & Campus
2027 What Is the Fastest Way to Become a Counselor?

2027 What Is the Fastest Way to Become a Counselor?
2027 Online Photography Degree Programs With No Personal Statement or Admissions Essay Required

2027 Online Photography Degree Programs With No Personal Statement or Admissions Essay Required
2027 Best Medical Assistant Schools & Programs in Rhode Island – How to Become a Medical Assistant in Rhode Island

2027 Best Medical Assistant Schools & Programs in Rhode Island – How to Become a Medical Assistant in Rhode Island
2027 Can a Music Education Degree Lead to Remote Jobs?

2027 Can a Music Education Degree Lead to Remote Jobs?
2027 Best Online Bachelor’s Degrees in Finance Programs

2027 Best Online Bachelor’s Degrees in Finance Programs
2027 Online vs. Traditional Accounting Degree Programs: Pros and Cons

2027 Online vs. Traditional Accounting Degree Programs: Pros and Cons
2027 Work Experience Requirements for Instructional Design & Education Technology Degree Master's Programs

2027 Work Experience Requirements for Instructional Design & Education Technology Degree Master's Programs
2027 Online Pediatric Nurse Practitioner Degree Programs With No Letters of Recommendation Required

2027 Online Pediatric Nurse Practitioner Degree Programs With No Letters of Recommendation Required