"The 1982 'A Number for your Thoughts' by Stephen P. Richards appears to have a doppelgänger in a 1986 version by Malcolm E. Lines. Does anybody know why the name changed?" The Stephen P. Richards authorship is pseudonymous. Malcolm E. Lines wrote the book, he explained to me: "when I was employed at Bell Labs, Murray Hill, NJ as a theoretical condensed matter theorist. Since I was regularly publishing research papers in various learned journals in the early 1980s, I decided to keep my book written for a wider readership totally apart from my formally more academic books and papers by writing it under a pseudonym. It also seemed a good idea not to let my employer know that I was 'wasting my time' on such sidelines." A second title that sports the Richards pseudonym is the 1987 'Numbers at Work and at Play' which was republished in 1990 by Lines under the title 'Think of a Number'.