Sandler, C., & Keefe, J. (2004). 1001 letters for all occasions: The best models for every business and personal need. Adams Media.
Chicago-viite (17. p.)Sandler, Corey, ja Janice Keefe. 1001 Letters for All Occasions: The Best Models for Every Business and Personal Need. Avon, Mass: Adams Media, 2004.
MLA-viite (9. p.)Sandler, Corey, ja Janice Keefe. 1001 Letters for All Occasions: The Best Models for Every Business and Personal Need. Adams Media, 2004.
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