Alastair Reynolds (one of my favorite hard sci-fi authors) used the idea a few times as well. Mostly as a minor detail, but “A Spy In Europa” had cities support

Alastair Reynolds (one of my favorite hard sci-fi authors) used the idea a few times as well. Mostly as a minor detail, but “A Spy In Europa” had cities supported by hyperdiamond vacuum balloons, which is a pretty great image.