Hero (1899). "Pneumatika, Book ΙΙ, Chapter XI". Herons von Alexandria Druckwerke und Automatentheater (in Greek and German). Wilhelm Schmidt (translator). Leipzig: B.G. Teubner. pp. 228–232.
Hero of Alexandria (1851). "Temple Doors opened by Fire on an Altar". Pneumatics of Hero of Alexandria. Bennet Woodcroft (trans.). London: Taylor Walton and Maberly (online edition from University of Rochester, Rochester, NY). Archived from the original on 2008-05-09. Retrieved 2008-04-23.
Hero of Alexandria (1851). "Temple Doors opened by Fire on an Altar". Pneumatics of Hero of Alexandria. Bennet Woodcroft (trans.). London: Taylor Walton and Maberly (online edition from University of Rochester, Rochester, NY). Archived from the original on 2008-05-09. Retrieved 2008-04-23.