This information might depend excessively on sources too carefully associated with the topic, probably preventing the posting from currently being verifiable and neutral. Afterwards, in 1991, Drexler, Peterson and Pergamit released A further book entitled “Unbounding the Future: the Nanotechnology Revolution” by which they use the terms “nanobots” or “assemblers” https://www.directivepublications.org/journal-of-applied-nanoscience/