Philippines. Bureau of Agricultural Research. (1990). On-farm research manual. Bureau of Agricultural Research, Department of Agriculture.
Chicago-referens (17:e uppl.)Philippines. Bureau of Agricultural Research. On-farm Research Manual. Quezon City: Bureau of Agricultural Research, Department of Agriculture, 1990.
MLA-referens (9:e uppl.)Philippines. Bureau of Agricultural Research. On-farm Research Manual. Bureau of Agricultural Research, Department of Agriculture, 1990.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.