Humphries, J. (1973). How to manage a sales team: A practical guide to sales leadership. Grolier.
Chicago-viite (17. p.)Humphries, John. How to Manage a Sales Team: A Practical Guide to Sales Leadership. Wachai, Hong Kong: Grolier, 1973.
MLA-viite (9. p.)Humphries, John. How to Manage a Sales Team: A Practical Guide to Sales Leadership. Grolier, 1973.
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