Gaya APA

Selected problems of co-operative development : international co-operative seminar 8th-17th 1975 Berastagi, North Sumatera Indonesia. (1976). : .

Gaya MLA

Selected problems of co-operative development : international co-operative seminar 8th-17th 1975 Berastagi, North Sumatera Indonesia. . : , 1976. Text.