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The first occurrence from the Frenchman Formation (late Maastrichtian) of juvenile ceratopsians (Chasmosaurinae) is reported here based on two postorbital horn-cores. The sutures confirm that the frontal attaches along the medial side of the postorbital much like that in Centrosaurinae and cannot be used as a tool for distinguishing the two ceratopsid subfamilies.
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Tim T. Tokaryk (1997) studied this question.
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