This paper describes of the basic concepts and current status of the ESO NTT Project. The NTT is an optical telescope with a primary mirror of 3.5 meters and two Nasmyth foci. It will operate at ESO's La Silla Observatory, and is planned for installation in 1988. The project combines a number of innovative technical solutions.
M. Tarenghi, M. Tarenghi,
"European Southern Observatory (ESO) 3.5m New Technology Telescope", Proc. SPIE 0628, Advanced Technology Optical Telescopes III, (20 August 1986); doi: 10.1117/12.963532; https://doi.org/10.1117/12.963532