\Bibitem{Fed51} \by V.~S.~Fedorov \paper Monogenic vector-functions.~I \jour Sb. Math. \yr 1951 \vol 71 \issue 1 \mathnet{http://mi.mathnet.ru//eng/sm5693} \mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=43223} \zmath{https://zbmath.org/?q=an:0043.15303}