http://avalonlibrary.net/Nikola_Tesla/Books/Secrets%20of%20Antigravity%20Propulsion.pdf

https://arxiv.org/pdf/physics/0211001.pdf

https://quantumantigravity.files.wordpress.com/2017/04/musha-biefeld-brown.pdf

https://en.wikipedia.org/wiki/Biefeld%E2%80%93Brown_effect

http://www.ttbrown.com/book_110203.html

https://corradomalanga.files.wordpress.com/2018/04/vymaanika-shaastra.pdf

https://pdfhost.io/v/57oxNVXni_VYMAANIKA_SHAASTRA_AERONAUTICSpdf.pdf