I found this paragraph in my textbook, "Analytical Mechanics" 6th Ed., Fowles and Cassiday. Buried in Appendix I, "Software Tools" :
"...many [mathematical software programs] suffer deficiencies common to most technical user manuals: frequently they are poorly organized and poorly written; almost invariably they are loaded with undefined cryptic jargon; critical information is sometimes buried away in unsuspected locations; and rarely do they perform well as a tutorial for the novice user. [...] the Mathematica manual is afflicted with most of the aforementioned ills. Indeed, its writers seem to have worked hard at rendering their otherwise excellent product unuseable. That is succumbs to these potential shortcomings should have been instantly obvious when we opened it. On turning over the gorgeous-looking cover of the extremely weighty manual to expose what we thought would be the first page, we found instead, much to our dismay, the last page written upside down! The book had been misbound! Fortunately, the text proved invariant under a 180 degree rotation of the x-axis. We guessed perhaps, that being in the business of mathematical computation, the manufacturer meant this as a test exercise for the novice user."