\Bibitem{Mor43} \by V.~Morosov \paper On a theorem of E.~Cartan \jour Sb. Math. \yr 1943 \vol 54 \issue 3 \mathnet{http://mi.mathnet.ru//eng/sm6165} \mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=9958} \zmath{https://zbmath.org/?q=an:0061.04706}