Gupta, P.K. Hand book of soil, fertilizer and manure / P.K. Gupta. - 1st ed. - New Delhi : Botanica Agro, 1999. - 431 p. : ill. ; 23 cm. ISBN: 8187167211 Subjects--Topical Terms: Soil mechanics. Dewey Class. No.: 631.4 / GUH