https://openlibrary.org/books/OL6245329M.opds Motivation and market behavior 2020-09-27T14:28:59Z Robert Ferber https://openlibrary.org/authors/OL135880A/Robert_Ferber R. D. Irwin Homewood, Ill 1958 437 p. eng https://openlibrary.org/books/OL6245329M https://archive.org/details/motivationmarket00ferb 542681 58005803