What does “SSM” stand for?
SSM stands for “So Spake Martin” which is a collection of answers and information that George has given during interviews, Q&A sessions at fan conventions and in correspondence. So Spake Martin is hosted and administrated by Westeros and I found most of this information through the Concordance of factual information section from The Citadel, also hosted by Westeros. An important point to note is that any information from SSM cannot be taken as 100% canon until it has appeared in the books. This is because the details are subject to rewrites or George simply forgetting something he said while he was thinking about it but did not actually write down. After all George cannot be expected to remember some random answer he gave during a Worldcon panel 10 years ago. However, because George said it this makes the information vastly more important and reliable than any other non-canon source and thanks to the way the SSM archive has been structured on Westeros there is an easy way to reference
