Subscribe | UPI Odd Newsletter Subscribe GAVLE , Sweden, Feb. 2 (UPI) -- A Swedish library said it received an anonymous package containing a book that went missing from the library more than 37 years ago. The Gavle library said "An Essay on Liberation," a Marxist tome by German philosopher Herbert Marcuse, was returned to the shelves Thursday after the anonymous borrower returned it, The Local reported Monday. Advertisement The last return date stamped inside the book was Nov. 11, 1971.