Speas, R. Dixon
Technical aspects of air transport management : operations, engineering and economic facators of airline services / R. Dixon Speas
MGraw-Hill , 1955
 Buku Teks
Pigou, Arthur Cecil, 1877-1959
Aspects economic history 1918-1925
MacMillan, 1947
 Buku Teks
Economic aspects of health
edited by Victor R. Fuchs
University of Chicago, 1982
 Buku Teks
Economic aspects of health services
edited by A.J. Culyer and K.G. Wright
Martin Robertson, 1978
 Buku Teks
Lewis, William Arthur, 1915-
Some aspects of economic development
University of Ghana by the Ghana Pub, 1971
 Buku Teks