H1 and ZEUS Results on Fcc(bar)2 and Fbb(bar)2

Recent results from the H1 and ZEUS collaborations on the contribution of heavy quarks to the inclusive proton structure function are presented. Measurements of the charm structure function Fcc(bar)2 are made mainly by explicit reconstruction of a D meson. The measurement of the inclusive beauty structure function Fbb(bar)2, and also Fcc(bar)2 , is made using precise information from silicon vertex detectors in order to reconstruct the impact parameter of tracks from the decay of the heavy hadron. The results are compared with the predictions of calculations based on perturbative QCD. (author)