Gregg, Davis Weiner
Group life insurance : an analysis of concepts, contracts, costs and company practices
University of Pennsylvania by R.D. Irwin, 1962
 Buku Teks
Waddams, S.M.
The Law of Contracts
Canada Law Book INC, 1984
 Buku Teks
Calamari, John D.
The law of contracts
West Publishing, 1987
 Buku Teks SO
Calamari, John D.
The law of contracts
West Publishing, 1987
 Buku Teks SO
Greeg, Davis W.
Group life insurance : an analysis of concepts, contracts, costs, and company practices / Davis W. Greeg
Richard D. Irwin, Inc., 1960
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