Hartmann, Reinhard R.K., author
Tubingen [Gunter Narr verlag] 1973
Buku Teks
Hartmann, Reinhard R.K., author
Beitrage, 1973
Buku Teks
Artikel Jurnal
Richman, Barry M.
McGraw-Hill, 1972
Buku Teks
Oettinger, Anthony G.
Harvard University Press , 1960
Buku Teks