@article{Schinzel_2014, title={On Fixed Divisors of Forms in Many Variables, I}, volume={114}, url={https://www.mscand.dk/article/view/17104}, DOI={10.7146/math.scand.a-17104}, abstractNote={Let $D_{d,r}$ be the maximal fixed divisor of a primitive form of degree $d$ in $r$ variables over $\mathsf{Z}$. A formula is given for $D_{d,2}$ and estimates for $D_{d,r}$ for $r>2$. As a consequence, a question of Nagell raised in 1919 is completely answered. }, number={2}, journal={MATHEMATICA SCANDINAVICA}, author={Schinzel, A.}, year={2014}, month={May}, pages={161–184} }