Popular Mechanics - Maio 1986

Popular Mechanics - Maio 1986

https://books.google.pt/books?id=QOQDAAAAMBAJ&printsec=frontcover&hl=pt-PT&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=true

Popular Aviation / Flying - Junho 1949

Popular Aviation / Flying - Junho 1949

https://books.google.pt/books?id=uUlZcyTdK7YC&printsec=frontcover&hl=pt-PT&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=true

Model Aviation - janeiro 1985

Model Aviation - janeiro 1985

http://library.modelaviation.com/ma/1985/1

RC Soaring Digest - Março 2007

RC Soaring Digest - Março 2007

http://www.rcsoaringdigest.com/pdfs/RCSD-2007/RCSD-2007-03.pdf

Grid Leaks - maio 1958

Grid Leaks - maio 1958

http://www.rclibrary.co.uk/files_titles/1604/Grid_Leaks_1958_05.pdf