00685nam a2200205Ia 4500 CTU_122920 210402s9999 xx 000 0 und d 630.9599 D213 Dar, William D. The interaction between research and extension in the context of farming systems development William D. Dar, Manuel F. Bonifacio Quezon City,Philippines Agricultural Training Institute 1990 Agriculture,Agricultural systems Research Philippines,Philippines Hiếu, Huỳnh Mai Trung tâm Học liệu Trường Đại học Cần Thơ