Harshbarger, Ronald J., author
Heath, 1990
Buku Teks
Love, Clyde E., author
Macmillan, 1943
Buku Teks
Jones, Andrew, author
Radcliffe Publishing, 2009
Buku Teks
Chow, Gregory C., author
McGraw-Hill, 1983
Buku Teks
Baltagi, Badi H. (Badi Hani), author
Springer, 2011
Buku Teks