 | Publishing Ltd. pp. 175–176. ISBN 1-904381-16-2. "L'affondamento del sommergibile britannico Upholder" [The sinking of the British submarine Upholder]... 16 KB (1,369 words) - 17:15, 8 August 2023 |
 | Submarine of the Porpoise class - Allied Warships of WWII - uboat.net". Sommergibile HMS Rorqual. HMS Rorqual, Uboat.net Caruana, Joseph (2012). "Emergency... 8 KB (827 words) - 20:10, 15 April 2024 |