Cross ratio geometry: advances for multiple collinear points in the desargues affine plane

This paper introduces advances in the geometry of the cross ratio of multiple collinear points of a skew field in the Desargues affine plane. This paper extends earlier results for three collinear points in terms of the geometry resulting from four co-linear points in the Desargues affine plane. The results given here have a clean rendition, based on Desargues affine plane axiomatics, skew field properties and the addition and multiplication of planar collinear points.