document.write("« Galilei Group with multiple central extension, vorticity and entropy generation: "Exotic" fluid in 3+1-dimensions. (arXiv:1707.03153v2 [hep-th] UPDATED)");document.write(" | ");document.write("Gauss-type formulas for link map invariants. (arXiv:1711.03530v1 [math.GT]) »");