D.Chamberlain, et al, "RT Essentials"
Publisher: O'Reilly | ISBN: 0596006683 | edition 2005 | PDF | 218 pages | 2,6 mb

In a typical organization, there's always plenty that to do such as: pay vendors, invoice customers, answer customer inquiries, and fix bugs in hardware or software. You need to know who wants what and keep track of what is left to do.