Kurek, Jan, and Włodzimierz M. Mikulski. 2004. “Higher Order Jet Prolongations Type Gauge Natural Bundles over Vector Bundles”. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica 4 (May):111-22. https://studmath.uken.krakow.pl/article/view/13313.