Found 1 pathways with zero (PubMed) references
* [http://classic.wikipathways.org/instance/WP27_r117323](http://classic.wikipathways.org/instance/WP27_r117323) 'Phenylalanine, tyrosine, and tryptophan biosynthesis' in Saccharomyces cerevisiae has zero references;
More details at https://www.wikipathways.org/WikiPathwaysCurator/ReferencesTests/atLeastOneReference