Polymastia penicillus. Site: S Green Island, Carlingford Lough
 Polymastia penicillus. Event number: 19840607/04. Site: S Green Island, Carlingford Lough. 1984-06-07. Photograph © Christine Howson. (1/3) 
 Christine Howson (2026). Photograph of Polymastia penicillus. Site: S Green Island, Carlingford Lough. [In] Marine Biodiversity Data Portal - NI.
https://habitas.org/mbdp/sitephoto.php?item=niss_6586.jpg. Accessed on 2026-11-04