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Original image by John D. Croft. Uploaded by Jan van der Crabben, published on 26 April 2012 under the following license: GNU Free Documentation License. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. Please note that content linked from this page may have different licensing terms.