Check out this website: Reflexvisier German aircraft gunsights
Examples:
EZ 42 Kreiselvisier EZ 42 | reflexvisier
Revi C12E Revi C12E | reflexvisier
Revi16D Revi 16 D | reflexvisier
Erwin Wiedmer, owner of this website also maintains deutscheluftwaffe.de
For the 004A: The Development of the Junkers Jumo 004B", Journal of Engineering Gas Turbines Power, 1997 Vol. 119 pp 783-789
For the 004B: "The Junkers Jumo 004 Jet Engine", Aircraft Engineering, 1946. Vol. 18, pp 10-17
From "The Development of the Junkers Jumo 004B", Journal of...