135 citations · 636 across the 19 of their papers we have counts for
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astro-ph2002★ 6 cited
Comparative Absorption and Emission Abundance Analyses of Nebulae: Ion Emission Densities for IC 418
Robert Williams, Edward B. Jenkins, Jack A. Baldwin +1
Recent analyses of nebular spectra have resulted in discrepant abundances from CNO forbidden and recombination lines. We consider independent methods of determining ion abundances…
astro-ph2002★ 27 cited
VLA Observations of H I in the Helix Nebula (NGC 7293)
Luis F. Rodriguez, W. M. Goss, Robert Williams
We report the detection of 21-cm line emission from H I in the planetary nebula NGC 7293 (the Helix). The observations, made with the Very Large Array, show the presence of a ring…