9. http://www.booksinc.net/NASApp/store/Product;jsessionid=abcF-ch09-pbU6m7ZRrLr?s=showproductandisbn=0765322166
11. http://www4.bookstore.washington.edu/_trade/ShowTitleUBS.taf?ActionArg=TitleandISBN=9780765322166
≅ SiSU Spine ፨ (object numbering & object search)
(web 1993, object numbering 1997, object search 2002 ...) 2024