The textbook is available in three variations: (1) as a web site; (2) as a PDF for computer viewing (with internal links); and, (3) as a PDF for printing (without links).
We provide here three versions of the textbook, two with minor revisions by James Foster at Walla Walla University (2020 and 2022) and the 2018 version from David J. Eck at Hobart and William Smith Colleges.