Bilinear Kakeya-Nikodym averages of eigenfunctions on compact Riemannian   surfaces
  We obtain an improvement of the bilinear estimates of Burq, G\'erard and Tzvetkov in the spirit of the refined Kakeya-Nikodym estimates of Blair and the second author. We do this by using microlocal techniques and a bilinear version of H\"ormander's oscillatory integral theorem. 
Changxing Miao, Christopher D. Sogge, Yakun Xi and Jianwei Yang
math.AP