OCLC Classify -- an Experimental Classification ServiceEnter an ISBN, OCLC#, UPC, or ISSN Standard Number: ISBN An ISBN is a unique number assigned to an item by its publisher. Each ISBN is a 10 or 13 digit number. Thirteen-digit ISBNs must begin with either 978 or 979. Enter ISBNs with our without hyphens. For example; 978-1-886101-11-1 9781886101111 1-886101-11-6 1886101116 OCLC # OCLC assigns a unique number to each bibliographic record input into
