published on 01 April 2014
Based on Wikipedia content that has been reviewed, edited, and republished. Original image by Pataki Márta. Uploaded by Mark Cartwright, published on 01 April 2014 under the following license: Creative Commons: Attribution-NonCommercial-ShareAlike. This license lets others remix, tweak, and build upon this content non-commercially, as long as they credit the author and license their new creations under the identical terms.
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