Gupta C.B, Ratna V, . (1973). Satistical Caculatons. New Delhi: Vikas Publication.
Gupta C.B, Ratna V, . 1973. Satistical Caculatons. New Delhi: Vikas Publication.
Gupta C.B, Ratna V, . Satistical Caculatons. New Delhi: Vikas Publication. 1973.
