• [Wiki] http://en.wikipedia.org/wiki/Raja_(genus).
• [AnAge] http://genomics.senescence.info/species/entry.php?species=Raja_clavata.
• [ADW] http://animaldiversity.ummz.umich.edu/accounts/Raja_clavata/.
• [Hold1972] Holden, M. J. (1972). The growth rates of Raja brachyura, R. clavata and R. montaqui as determined from tagging data. J. Physiol. (Lond.), 34:161--168.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.