Snow, Barbara (1960-10-01). "The Breeding Biology of the Shag Phalacrocorax Aristotelis on the Island of Lundy, Bristol Channel". Ibis. 102 (4): 554–575. doi:10.1111/j.1474-919x.1960.tb07132.x. ISSN1474-919X.
Harris, M. P.; Wanless, S. (1991). "The Importance of the Lesser Sandeel Ammodytes marinus in the Diet of the Shag Phalacrocorax aristotelis". Ornis Scandinavica (Scandinavian Journal of Ornithology). 22 (4): 375–382. doi:10.2307/3676511. JSTOR3676511.
Harris, M. P.; Wanless, S. (1991). "The Importance of the Lesser Sandeel Ammodytes marinus in the Diet of the Shag Phalacrocorax aristotelis". Ornis Scandinavica (Scandinavian Journal of Ornithology). 22 (4): 375–382. doi:10.2307/3676511. JSTOR3676511.
Snow, Barbara (1960-10-01). "The Breeding Biology of the Shag Phalacrocorax Aristotelis on the Island of Lundy, Bristol Channel". Ibis. 102 (4): 554–575. doi:10.1111/j.1474-919x.1960.tb07132.x. ISSN1474-919X.