[1]. Kenna, R., Berche, B. (2012)." Managing Research Quality: Critical Mass and Optimal Academic Research Group Size", IMA Journal of Management Mathematics, 23, 195−207.
[2]. Engels, T. C. E., Dexters, N., Houben, B. (2012). "Correlations of Assessments of Research Group Quality and Productivity with Group Size, Output Numbers, And Normalized Impact, Proceedings of the 17th Science and Technology Indicators Conference", 247-257.
[3]. Price, D. S., Beaver, D. (1966). "Collaboration in an Invisible Collage", American Psychologist, 21, 1011-1018.
[4]. Qurashi, M. M. (1972).The Optimum Size of Research Pups for Maximum Effectiveness. Part 111. The Dependence of Scientific Output on the Size of Research Groups of Laboratories and Verification of Size Parameters in Parkinsonian law", Proceedings of the Pakistan Academy of Sciences, 9, 109-117.
[5]. Willmark, J. T., Eckerstein,S.,Langered,B. (1973)."The Iincrease in Efficiency with Size of Research Teams", IEEE Trans. Eng. Manag., EM-20, 80-86.
[6]. Daley, R. C. (1978). "The Role of Team and Task Characteristics in R & D Team Collaborative Problem Solving and Productivity", Management Science, 24, 1579-1588.
[7].Stankiewicz, R. (1979)."The Size and Age of Swedish Academic Research Group and their Scientific Performance, Andrews, F. M. (ed.)", Scientific Productivity, New York, Cambridge University Press.
[8]. Cohen, J. E. (1991). "Size, Age and Productivity of Scientific and Technical Research Groups", Scientometrics, 20, 395-416.
[9]. Halperin, M. R., Chakrabarti, A. K. (1987). "Firm and Industry Characteristics Influencing Publications of Scientists in Huge American Companies", R & D Management, 17, 167-173.
[10]. Wallmaik, J. T., Sellerberg, B. (1966). "Efficiency vs .Size of Research Teams", IEEE Trans. Eng. Manag., EM-13, 137-142.
[11]. Kenna, R., Berche, B. (2011)." Critical Masses for Academic Research Groups and Consequences for Higher Education Research Policy And Management", Higher Education Management and Policy, 23, 9-29.
[12]. Kenna, R., Berche, B. (2010)." The Extensive Nature of Group Quality", Europhysics Letters, 90, 1-6.
[13]. Kenna, R., Berche, B. (2011). "Critical Mass and the Dependency of Research Quality on Group Size", Scientometrics, 86, 527-540.
[14]. Aghamohammadi, A., Abolhassani, H., Latif, A., Tabassomi, F., Shokuhfar, T., Torabi Sagvand, B., Shahinpour, S., Mirminachi, B., Parvaneh, N., Movahedi, M., Gharagozlou, M., Sherkat, R., Amin, R., Aleyasin, S., Faridhosseini, R., Jabbari-Azad, F., Cheraghi, T., Eslamian, M. H., Khalili, A., Kalantari, N., Shafiei, A., Dabbaghzade, A., Khayatzadeh, A., Ebrahimi, M., Razavinejad, D., Bazregari, S., Ebrahimi, M., Ghaffari, J., Bemanian, M. H., Behniafard, N., Kashef, S., Mohammadzadeh, I., Hammarström, L., Rezaei, N. (2014). "Long-Term Evaluation of a Historical Cohort of Iranian Common Variable Immuno- Deficiency Patients", Expert Rev Clin Immunol, 10, 1405-1417.