In this paper we study Moufang-Klingenberg planes M (A) defined over a local alternative ring A of dual numbers. We show that some collineations of M (A) preserve cross-ratio and thus establish a relation between harmonicity and harmonic position.
ÇELİK, BASRİ; AKPINAR, ATİLLA; and ÇİFTÇİ, SÜLEYMAN
"On harmonicity in some Moufang-Klingenberg planes,"
Turkish Journal of Mathematics: Vol. 34:
2, Article 9.
Available at: https://journals.tubitak.gov.tr/math/vol34/iss2/9