"piethein.com". Archived 4 August 2010 at the Wayback Machine "For a long time they appeared under the signature Kumbel Kumbell. Here is the reason why: Piet is the Dutch form of the name Peter or Petrus, which means rock, stone, and Hein is a way of spelling 'hen', the old Danish word for a whetstone. 'Kumbel', or 'kumbl' as it strictly speaking should be written, also means stone, though more a grave monument. In other words, Piet Hein, or Stone Stone can, in a way, be translated by Kumbel Kumbel. He originally wrote the second word with two Ls, also later the signature became just Kumbel – the name he is at least as well known by as his own." (به انگلیسی). Archived from the original on 4 August 2010. Retrieved 26 July 2022.{{cite web}}: نگهداری یادکرد:ربات:وضعیت نامعلوم پیوند اصلی (link)
