On the torsion of rational elliptic curves over quartic fields
  Let E be an elliptic curve defined over Q and let G = E(Q)_tors be the associated torsion subgroup. We study, for a given G, which possible groups G <= H could appear such that H=E(K)_tors, for [K:Q]=4 and H is one of the possible torsion structures that occur infinitely often as torsion structures of elliptic curves defined over quartic number fields. 
Enrique Gonzalez-Jimenez, Alvaro Lozano-Robledo
math.NT math.AG