Sinha, R.R.P. , Mishra, B.K. and Hasson, M.K. 1975. Birth-order and need for achievement in tribals and non-tribals. Indian Journal of Psychiatric Social Work. 4, 1 (Jul. 1975), 26–32. DOI:https://doi.org/10.29120/ijpsw.1974.v4.i1.47.