Παραπομπή APA

Siebert, H. (1998). Redesigning social security. Tübingen.

Παραπομπή Chicago Style

Siebert, Horst. Redesigning Social Security. Tübingen, 1998.

Παραπομπή MLA

Siebert, Horst. Redesigning Social Security. Tübingen, 1998.