Abundances of Disk Planetary Nebulae in M31 and the Radial Oxygen
  Gradient
  We have obtained spectra of 16 planetary nebulae in the disk of M31 and
determined the abundances of He, N, O, Ne, S and Ar. Here we present the median
abundances and compare them with previous M31 PN disk measurements and with PNe
in the Milky Way. We also derive the radial oxygen gradient in M31, which is
shallower than that in the Milky Way, even accounting for M31's larger disk
scale length.
