SNOBOL4+ user notes - Information for people having documentation for the Vanilla SNOBOL programming language and wishing to use SNOBOL4+. By Michael Davis. - http://www.sachsdavis.clara.net/Snobol4Pdoc.html
SNOBOL Language Web Page - Introduction to SNOBOL Programming Language. - http://cs.fit.edu/~dclay/cse5040/snobol.html
SNOBOL4 Resources - Information and links about SNOBOL4. - http://www.snobol4.org/
Macro Implementation of SNOBOL4 in C - A port of Macro SNOBOL4 (The original Bell Telephone Labs implementation, written in SIL macros) for machines with 32-bit (or larger) pointers. Supports full SNOBOL4 language plus SPITBOL and other extensions. - http://www.snobol4.org/csnobol4/