The relationship between the exponential mass ratio (Tsiolkovsky rocket equation) and the physical size of rockets is a foundational principle of aerospace engineering and does not require empirical citation.
The claim states a fundamental physical and mathematical reality of rocketry governed by the Tsiolkovsky rocket equation, where exponential propellant requirements dictate large vehicle structures. As this is a basic, definitive tenet of orbital mechanics and everyday aerospace engineering observation, it is classified as common knowledge requiring no citation.