Bekar, MuratYayli, Yusuf2024-02-232024-02-2320130188-70091661-4909https://doi.org/10.1007/s00006-012-0376-yhttps://hdl.handle.net/20.500.12452/10812An involution or anti-involution is a self-inverse linear mapping. Involutions and anti-involutions of real quaternions were studied by Ell and Sangwine [15]. In this paper we present involutions and antiinvolutions of biquaternions (complexified quaternions) and split quaternions. In addition, while only quaternion conjugate can be defined for a real quaternion and split quaternion, also complex conjugate can be defined for a biquaternion. Therefore, complex conjugate of a biquaternion is used in some transformations beside quaternion conjugate in order to check whether involution or anti-involution axioms are being satisfied or not by these transformations. Finally, geometric interpretations of real quaternion, biquaternion and split quaternion involutions and anti-involutions are given.eninfo:eu-repo/semantics/closedAccessReal QuaternionsBiquaternions (Complexified Quaternions)Split QuaternionsInvolutionsAnti-InvolutionsArticle2322832992-s2.0-84878107492Q3WOS:000319165000001Q410.1007/s00006-012-0376-y