Gundam's mobile suits grew from the powered armour of Heinlein's Starship Troopers, popularised in Japan by Studio Nue's illustrations for the 1977 translation.
Book· 1959· Science Fiction
Starship Troopers
Starship Troopers: 1 recorded work traces back to it.
What Starship Troopers influenced
Works that record this one as a source, with the evidence a contributor gave.