It's probably Norma-52. I have the same. On the burner is signed "Norma D.R.P. Germany" and on the tank "Norma [G.B.] Norma [G.B.] Nur fur spiritus". The year of production unknown. It has also small aluminium plate between the burner and tank: on the red background white letters - B. Barthel, [G.B.], Norma 52. Hope it would help Best regards sgt.Hicks