Παραπομπή APA

Gurmel Singh, Joshy, B. P., & Venkata Ramanan. (1990). Manual of soil and water conservation practices (lost).

Παραπομπή Chicago Style

Gurmel Singh, B P. Joshy, και Venkata Ramanan. Manual of Soil and Water Conservation Practices (lost). NewDelhi, Oxford, 1990.

Παραπομπή MLA

Gurmel Singh, et al. Manual of Soil and Water Conservation Practices (lost). 1990.