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., editor
The Law of Contracts
Canada Law Book INC, 1984
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Calamari, John D.
The law of contracts
West Publishing, 1987
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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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Eisenberg, Melvin A.
Contracts Gilbert law summaries
Harcourt Brace, 1994
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