ATLA Catholic Periodical and Literature IndexATLA Catholic Periodical and Literature Index® (ATLA CPLI®) is provides indexing of periodicals, essay collections, church documents, papal documents and electronic resources expressly addressing the practice and intellectual tradition of Roman Catholicism. Content within its scope is selected for indexing based on enduring scholarly merit. ATLA CPLI contains indexing from 1981 to the present and is updated quarterly. ALTA CPLI now combined with ATLA Religion Database with Alta Series.