His PC world 1-2-3 for Windows complete handbook, c1991: t.p. (John Walkenbach) p. iii (Ph. D., Univ. of Montana; contributing editor for PC world and Info world)

Microsoft Excel 2000 power ... 1999: CIP t.p. (John Walkenbach) data sh. (b. 02-16-52)

101 Excel 2013 tips, tricks & timesavers, 2013: t.p. (John Walkenbach) p. iii (a leading authority on spreadsheet software; author of more than 50 spreadsheet books; graduated from the University of Missouri, Masters and PhD from the University of Montana)