The publishing and editorial teams would like to thank the following, for their invaluable service as 2021 reviewers for this journal. We are very grateful for the contributions made. With their help, the journal has been able to publish such high-quality articles:
| Aarif, Md. Bokhtiar Hasan |
| Abakah, Emmanuel Joel Aikins |
| Abbas, Faisal |
| Abdoh, Hussein |
| Abdullah, Hariem |
| Abdullah, Mohammad |
| Acharya, Sanjeev |
| Afrifa, Godfred |
| Ahmed, Wajid |
| Ajmal, Hamza |
| Ajmal, Muhammad Mobeen |
| Akgün, Ali İhsan |
| Akoto, linda |
| Al-Faryan, Mamdouh Abdulaziz Saleh |
| Al-Fayoumi, Nedal |
| Al-Malkawi, Husam-Aldin |
| Al-Okaily, Manaf |
| Albada, Ali |
| Aleenajitpong, Natdanai |
| Ali, Shoaib |
| Almustafa, Hamza |
| Anarfo, Ebenezer |
| Asiaei, Kaveh |
| Aslam, Faheem |
| Athari, Seyed Alireza |
| Atif, Muhammad |
| Ayadi, Mohamed |
| Badru, Bazeet |
| Bai, Min |
| Baldan, Cinzia |
| Bandyopadhyay, Arindam |
| Banerjee, Pradip |
| Barros, Victor |
| Ben Saad, Sourour |
| Bhan, Ibna |
| Bhuiyan, Md. Borhan Uddin |
| Bian, Yuli |
| Boasiako, Kwabena |
| Bouri, Elie |
| Bouteska, Ahmed |
| Bressan, Aureliano |
| Bu, Qiang |
| Buertey, Samuel |
| Canil, Jean |
| Caporale, Guglielmo Maria |
| Chadha, Gurmani |
| Chakrabarti, Gagari |
| Chakrabarti, Prasenjit |
| Chancharat, Nongnit |
| Chatterjee, Devlina |
| Chaudhry, Neeru |
| Chauhan, Yogesh |
| Cheng, Yirung |
| Cheung, Adrian (Wai Kong) |
| Cho, Eunho |
| Chow, Yee Peng |
| Chung, Chien-Ping |
| Cotton, Deborah |
| Crisóstomo, Vicente |
| Cui, Xin |
| Dahiya, Monika |
| Dalwai, Tamanna |
| Danila, Nevi |
| Daniliuc, Sorin |
| Danlami, Muhammad Rabiu |
| Desai, Rajesh |
| Dhole, Sandip |
| Do, Trung K. |
| Doan, Ngocthang |
| Doan, Trang |
| Donadelli, Michael |
| Doyle, Joanne |
| Duppati, Geeta |
| Dutta, Anupam |
| Eldeeb, Mohamed |
| Enkhtaivan, Bolortuya |
| Fan, Hong |
| Fan, Rui |
| Fan, Zhenjun |
| Farooq, Umar |
| Fassas, Athanasios |
| Fauzi, Rizaldi |
| Foong, Swee-Sim |
| Gama, Paulo |
| Ganguly, Kousik |
| Gao, Ya |
| Ghalke, Avinash |
| Giri, Gayathri |
| Glabadanidis, Paskalis |
| Guidi, Francesco |
| Gunasekarage, Abeyratna |
| Gupta, Gaurav |
| Gupta, Ranjan |
| Haque, Tariq |
| Harakeh, Mostafa |
| Hasan , Mudassar |
| Hasan, Fakhrul |
| Hasan, Rajib |
| Hendijani Zadeh, Mohammad |
| Hendijani Zadeh, Mohammad |
| Hoang, Khanh |
| Hobbs, Jeffrey |
| Hu, Jun |
| Huang, He |
| Huang, Peng |
| Hull, Robert |
| Hung, Ngo |
| Jadiyappa, Nemiraja |
| Jiranyakul, Komain |
| Jiraporn, Pornsit |
| Joo, Young C. |
| Joseph, Anto |
| Kakani, Ram Kumar |
| Kang, Mhin |
| Kanuri, Srinidhi |
| Karafiath, Imre |
| Karim, Sitara |
| Karpavicius, Sigitas |
| Katti, Supriya |
| Ke, Yun |
| Khadivar, Hamed |
| Khalfan, Twahir |
| Khan, Muhammad Arif |
| Kong, Dongmin |
| Kulshreshtha, Kushagra |
| Kumar, Rajesh |
| Kumar, Vijay |
| Lee, Doowon |
| Li, Frank |
| Li, Jialong |
| Li, Shihe |
| Li, Yi-Hua |
| Li, Zhaohua |
| Liao, Jing |
| Lisboa, Inês |
| Liu, Chelsea |
| Lo, Chien-Ling |
| Lu, Yue |
| Lu, Yue |
| Ma, Liangbo |
| Ma, Rui |
| Machokoto, Michael |
| Mahendru, Mandeep |
| Maung, Min |
| Mishra, Nandita |
| Mohd Rashid, Rasidah |
| Mohd Roslen, Siti Nurhidayah |
| Mushinada, Venkata Narasimha Chary |
| Naeem, Muhammad Abubakr |
| Nanayakkara, Madurika |
| Nawn, Samarpan |
| Neves, Maria Elisabete |
| Newaz, Mohammad |
| Nguyen, Duy |
| Nguyen, Viet-Dung |
| Ofori-Sasu, Daniel |
| Omura, Akihiro |
| Pal, Abhinav |
| Pan, Zheyao |
| Panta, Humnath |
| Pathak, Rajesh |
| Pathak, Rajesh |
| Portal, Márcio |
| Purda, Lynnette |
| Qasem, Ameen |
| Rahman, Anisur |
| Rainville, Megan |
| Rehman, Mobeen Ur |
| Rubbaniy, Ghulame |
| Sahoo, Pradipta Kumar |
| Sakawa, Hideaki |
| Salerno, Dario |
| Sen, Chitrakalpa |
| Shan, Yuan |
| Shao, Xue-Feng |
| Sharma, Gunjan |
| Sheikh, Shahbaz |
| Shijin, Santhakumar |
| Simplice, Asongu |
| Singh, Vivek |
| Sisodia, Garima |
| Soccorsi, Stefano |
| Song, Jeong Seop |
| Sualihu, Mohammed Aminu |
| Subramaniam, Ravichandran |
| Sui, Cong |
| Sun, Jerry |
| Syriopoulos, Konstantinos |
| Talukdar, Bakhtear |
| Tan, Siow-Hooi |
| Tan, Weiqiang |
| Tan, Yongxian |
| Tchuigoua, Hubert Tchakoute |
| Teodósio, João |
| Terceño, Antonio |
| Thosar, Satish |
| Ting, Irene Wei Kiong |
| Tiwari, Chandan |
| To, Thomas Y. |
| Tran, Quoc Trung |
| Tzeremes, Panayiotis |
| Ujah, Nacasius |
| Vieira, Elisabete |
| Vogel, Julian |
| Wang, Carol |
| Wang, Kun Tracy |
| wattanatorn, woraphon |
| Weng, Tzu-Ching |
| Wilson, Linus |
| Xu, Fangming |
| Xu, Limin |
| Xue, Fujing |
| Yadav, Miklesh |
| Yang, Jin Young |
| Yarram, Subba |
| Yawson, Alfred |
| Yong, Hue |
| Younas, Zahid |
| Yu, Jeffrey |
| Zaynutdinova, Gulnara R. |
| Zhang, Weike |
| Zhao, Kevin |
| zhou, Fuzhao |
| Zhu, Caroline |