Columbia subject headings:
Harvard subject headings:
Bomb reconnaissance--Technological innovations.
Bombings--Prevention--Technological innovations.
Explosives--Additives
Explosives--Analysis.
Gunpowder, Smokeless.
Gunpowder.
Princeton subject headings:
Bomb reconnaissance--Technological innovations.
Bombings--Prevention--Technological innovations.
Explosives--Additives.
Explosives--Analysis.
Gunpowder, Smokeless.
Gunpowder.