Helgeson, D. V. (1985). Handbook for writing technical proposals that win contracts. Prentice-Hall.
Chicago Style aipamenaHelgeson, Donald V. Handbook for Writing Technical Proposals That Win Contracts. Englewood Cliffs, N.J: Prentice-Hall, 1985.
MLA aipamenaHelgeson, Donald V. Handbook for Writing Technical Proposals That Win Contracts. Prentice-Hall, 1985.
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