English, M; Kaplan, G; Rogers, LJ (2014). 《Is painting by elephants in zoos as enriching as we are led to believe?》. 《PeerJ》 2. e471쪽. doi:10.7717/peerj.471. PMC4103097. PMID25071994.
Matsuura, Keiichi (2015년 1월 1일). 《A new pufferfish of the genus Torquigener that builds "mystery circles" on sandy bottoms in the Ryukyu Islands, Japan (Actinopterygii: Tetraodontiformes: Tetraodontidae)》. 《Ichthyological Research》 62. 207–212쪽. Bibcode:2015IchtR..62..207M. doi:10.1007/s10228-014-0428-5. ISSN1616-3915. S2CID254164102.
Matsuura, Keiichi (2015년 1월 1일). 《A new pufferfish of the genus Torquigener that builds "mystery circles" on sandy bottoms in the Ryukyu Islands, Japan (Actinopterygii: Tetraodontiformes: Tetraodontidae)》. 《Ichthyological Research》 62. 207–212쪽. Bibcode:2015IchtR..62..207M. doi:10.1007/s10228-014-0428-5. ISSN1616-3915. S2CID254164102.
English, M; Kaplan, G; Rogers, LJ (2014). 《Is painting by elephants in zoos as enriching as we are led to believe?》. 《PeerJ》 2. e471쪽. doi:10.7717/peerj.471. PMC4103097. PMID25071994.
Matsuura, Keiichi (2015년 1월 1일). 《A new pufferfish of the genus Torquigener that builds "mystery circles" on sandy bottoms in the Ryukyu Islands, Japan (Actinopterygii: Tetraodontiformes: Tetraodontidae)》. 《Ichthyological Research》 62. 207–212쪽. Bibcode:2015IchtR..62..207M. doi:10.1007/s10228-014-0428-5. ISSN1616-3915. S2CID254164102.
Matsuura, Keiichi (2015년 1월 1일). 《A new pufferfish of the genus Torquigener that builds "mystery circles" on sandy bottoms in the Ryukyu Islands, Japan (Actinopterygii: Tetraodontiformes: Tetraodontidae)》. 《Ichthyological Research》 62. 207–212쪽. Bibcode:2015IchtR..62..207M. doi:10.1007/s10228-014-0428-5. ISSN1616-3915. S2CID254164102.