XII. Milletlerarası Türk Kooperatifçilik Kongresi Ankara 15-17 Aralık 1987 Tebliğler = XII. International Turkish Cooperative Congress Ankara 15-17 December, 1987 Papers = XII. Turkischer Internationaler Genossenschafts Kongress Ankara 15-17 Dezember 1987, Beitraege (Turkish Cooperative Association Publication No.; 68, 1987)