SWI-Prolog reference manual
SWI-Prolog binding to libarchive SWI-Prolog BerkeleyDB interface SWI-Prolog C-library Constraint Query Language A high level interface to SQL databases SWI-Prolog HTTP support SWI-Prolog binding to BSD libedit SWI-Prolog Natural Language Processing Primitives SWI-Prolog ODBC Interface SWI-Prolog support for PDT Pengines: Web Logic Programming Made Easy A C++ interface to SWI-Prolog SWI-Prolog Source Documentation Version 2 Prolog Unit Tests Google's Protocol Buffers Library SWI-Prolog RDF parser SWI-Prolog binding to GNU readline SWI-Prolog Semantic Web Library 3.0 SWI-Prolog SGML/XML parser SWI-Prolog SSL Interface Managing external tables for SWI-Prolog Transparent Inter-Process Communications (TIPC) libraries SWI-Prolog Unicode library SWI-Prolog binding to zlib
A paperback version of the manual is available.