International Standard Book Numbers

In 1968-72 all books published throughout the world began to receive coded ten-digit numerical labels called International Standard Book Numbers (ISBN's). For example, the ISBN of the text Multivariable Mathematics by Williamson and Trotter is 0-13-604835-8, as you may confirm on the back of the title page. The leading digit, 0, means that the book is published in the English-speaking world. The next group of digits, 13, identifies the publisher (in this case, Prentice-Hall). The publisher has chosen an identifying number of 604835 for this particular title.