Crampon, Jean E. 1988. Murphy, Parkinson, and Peter: Laws for librarians. Library Journal 113. no. 17 (October 15), p. 41.
Various forms, often credited as Westheimer’s Discovery – other forms include:
A month in the laboratory can often save an hour in the library.
UCLA Library http://wwwstage.library.ucla.edu/libraries/sel/12451.cfm
Why spend a day in the library when you can learn the same thing by working in the laboratory for a month?
Frank H. Westheimer, major figure in 20th century chemistry, dies at 95 http://news.harvard.edu/gazette/story/2007/04/frank-h-westheimer-major-figure-in-20th-century-chemistry-dies-at-95/, Harvard Gazette, April 19, 2007
Some version perhaps found in 1979 interview, Frank H. Westheimer http://www.chemheritage.org/discover/collections/oral-histories/details/westheimer-frank-h.aspx, Oral Histories, Chemical Heritage Foundation, in chapter “Research Projects and Philosophy”, p. 63, topic “Reading the literature.”