Villegas, L. M. (1977). Field demostration: Its effects on level of knowledge, understanding and ittitudes of farmers about choice of a rice variety and use of fertilizers [microform]. Photoduplication Service. University of the Philippines Library.
Lua i Stíl Chicago (17ú heag.)Villegas, Leopoldo M. Field Demostration: Its Effects on Level of Knowledge, Understanding and Ittitudes of Farmers About Choice of a Rice Variety and Use of Fertilizers [microform]. Quezon City: Photoduplication Service. University of the Philippines Library, 1977.
Lua MLA (9ú heag.)Villegas, Leopoldo M. Field Demostration: Its Effects on Level of Knowledge, Understanding and Ittitudes of Farmers About Choice of a Rice Variety and Use of Fertilizers [microform]. Photoduplication Service. University of the Philippines Library, 1977.