Merge pull request #1456 from weakish/Programming-in-Standard-ML-97

Add Programming in Standard ML '97

free-programming-books.md

@@ -1801,7 +1801,7 @@ See also [TeX](#tex)
 
 ### Standard ML
 * [Programming in Standard ML, Draft](http://www.cs.cmu.edu/~rwh/smlbook/) - Robert Harper
-
+* [Programming in Standard ML '97](http://www.dcs.ed.ac.uk/home/stg/NOTES/), by Stephen Gilmore, University of Edinburgh
 
 ### Subversion
 * [Subversion Version Control](http://www.phptr.com/content/images/0131855182/downloads/Nagel_book.pdf) (PDF)