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! Rygh <br> 1885 !! Petersen <br> 1919 !! Wheeler <br> 1927 !! Oakeshott <br> 1960 !! Jones <br> 2002 !! Compendium <br> Type
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|<!--1885--> [[File:R493.jpg|none|50px|Rygh 493]] Rygh 493