It means that the printed version was manually re-constructed from the original working version. The author here probably just had a hex dump which he'd hand as

It means that the printed version was manually re-constructed from the original working version. The author here probably just had a hex dump which he'd hand assembled, and re-wrote it to be more comprehensible in a text editor. This happened more often than you'd think. Before the widespread use of modems or other long-distance ways of sending digital data, it was often very difficult to transfer a digital version from one model of computer to another, let alone converting that format to something that a typesetting system could read. I remember listings in magazines that were clearly typeset manually from people who were just reading and re-typing from an original printout. Bear in mind that the reader was also expected to type the program by hand from the magazine. Generally the final proofreading was left to the person brave enough to type it all in again. It could be very frustrating to be faced with a program that was clearly exactly the same as the printed copy, but didn't run. On the other hand, it did teach you to be sceptical of what you read in magazines.