PACS numbers

42.60.Pk Continuous operation

V.F. Kitaeva, A.N. Odintsov, N.N. Sobolev “Continuously operating argon ion lasers” Sov. Phys. Usp. 12 699–730 (1970)
42.55.Lt, 42.60.By, 42.60.Pk, 42.60.Jf, 42.79.Bh, 42.60.Lh (all)