NGC 604 — A Giant H II Region Dominated by Many WR Stars
NGC 604, the largest H II region in M 33, is comparable in many respects (eg. ionized mass, total extent of a few hundered pc) with the giant H II complex 30 Doradus of the LMC. Recently D’Odorico and Rosa (1981) discovered broad WR emission features at 4640 Å, 4660 Å, He II 4686 Å and 5812 Å in a number of the bright knots in the core of NGC 604. In that paper it was concluded, that about 50 WR stars, mainly of the transition type WN 7 but WC characteristica seen as well, are present in the H II region. These findings were confirmed by the observations by Conti and Massey (1981).