Friedrich Kottler, Translation:On the spacetime lines of a Minkowski world…
“ Here, the line integral is orbiting around the normal in the negative sense, thus clock-wise if the coordinate system is a right-system; because by § 1 the directions , , are following each other like the coordinate axes, where is the normal (which is directed outwards of the area framed on ) of the framing-. Ordinarily, one prefers a positive sense of circulation and therefore the generalized rotation: etc. ”
