Conway Morris, Simon (2008). "A Redescription of a Rare Chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada". Journal of Paleontology. 82 (2): 424–430. Bibcode:2008JPal...82..424M. doi:10.1666/06-130.1. ISSN0022-3360. S2CID85619898.
Conway Morris, Simon (2008). "A Redescription of a Rare Chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada". Journal of Paleontology. 82 (2): 424–430. Bibcode:2008JPal...82..424M. doi:10.1666/06-130.1. ISSN0022-3360. S2CID85619898.
Conway Morris, Simon (2008). "A Redescription of a Rare Chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada". Journal of Paleontology. 82 (2): 424–430. Bibcode:2008JPal...82..424M. doi:10.1666/06-130.1. ISSN0022-3360. S2CID85619898.
Conway Morris, Simon (2008). "A Redescription of a Rare Chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada". Journal of Paleontology. 82 (2): 424–430. Bibcode:2008JPal...82..424M. doi:10.1666/06-130.1. ISSN0022-3360. S2CID85619898.