Current technical documentation on GLIF3 can be found on the InterMed web-site at Stanford University.
Specification documents
The full and final GLIF3 specification (GLIF 3.5) is provided here [Note that this may take a while to download due to its length].
A short 5 page description of GLIF 3.0 may be
found in the following Technical Report
Ontology
Download the GLIF 3.5 ontology schema and the GLIF 3.5 graph widget to used with the Protege knowledge-base editing software. Consult Protege documentation and GLIF 3.5 specifications on use.