Bader. (1970). The Integration of The State Insurance Into The Economic System of The German Democratic Republic. The Institute of National Planning.
Չիկագոյի ոճի (17րդ խմբ.) մեջբերումBader. The Integration of The State Insurance Into The Economic System of The German Democratic Republic. Cairo: The Institute of National Planning, 1970.
MLA (9րդ խմբ.) ՄեջբերումBader. The Integration of The State Insurance Into The Economic System of The German Democratic Republic. The Institute of National Planning, 1970.