Torsion subgroups of elliptic curves over quintic and sextic number   fields
  Let $\Phi^\infty(d)$ denote the set of finite abelian groups that occur infinitely often as the torsion subgroup of an elliptic curve over a number field of degree $d$. The sets $\Phi^\infty(d)$ are known for $d\le 4$. In this article we determine $\Phi^\infty(5)$ and $\Phi^\infty(6)$. 
Maarten Derickx and Andrew V. Sutherland
math.NT