Settler of the Galaxy: The CSU Solution to GTOC-X
https://www.researchgate.net/publication/335390088_SETTLER_OF_THE_GALAXY_THE_CSU_SOLUTION_TO_GTOCX
Stellar Engines: Design Considerations for Maximizing Acceleration
https://www.sciencedirect.com/science/article/pii/S0094576519312457
Galactic Habitability Re-Examined: Indications of Bimodality
https://arxiv.org/abs/1909.01742