List of rotorcraft used in World War II (English Wikipedia)

Analysis of information sources in references of the Wikipedia article "List of rotorcraft used in World War II" in English language version.

refsWebsite

Global rank English rank

7,636^th place

6,829^th place

airvectors.net

Goebel, Greg. "European Helicopter Pioneers." vectorsite.net. Retrieved: 10 October 2015.^{[unreliable source?]}