American University (Washington, D.C.). Foreign Area Studies, & Nyrop, R. F. (1986). The Yemens: Country studies (2nd ed.). American University, Foreign Area Studies : For sale by the Supt. of Docs., U.S. G.P.O..
Παραπομπή σε μορφή Chicago (17η εκδ.)American University (Washington, D.C.). Foreign Area Studies, και Richard F. Nyrop. The Yemens: Country Studies. 2nd ed. Washington, D.C.: American University, Foreign Area Studies : For sale by the Supt. of Docs., U.S. G.P.O., 1986.
Παραπομπή σε μορφή MLA (8th εκδ.)American University (Washington, D.C.). Foreign Area Studies, και Richard F. Nyrop. The Yemens: Country Studies. 2nd ed. American University, Foreign Area Studies : For sale by the Supt. of Docs., U.S. G.P.O., 1986.
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