APA

Gupta S. P., . (1997). Statistical methods. : Sultan Chand & Sons, New Delhi.

Chicago

Gupta S P, . 1997. Statistical methods. : Sultan Chand & Sons, New Delhi.

Harvard

Gupta S. P., . (1997). Statistical methods. : Sultan Chand & Sons, New Delhi.

MLA

Gupta S P, . Statistical methods. : Sultan Chand & Sons, New Delhi. 1997.