1. First Demonstration of ECHO: an External Calibrator for Hydrogen Observatories. (1st February 2017) Authors: Jacobs, Daniel C.; Burba, Jacob; Bowman, Judd D.; Neben, Abraham R.; Stinnett, Benjamin; Turner, Lauren; Johnson, Kali; Busch, Michael; Allison, Jay; Leatham, Marc; Rodriguez, Victoria Serrano; Denney, Mason; Nelson, David Journal: Publications of the Astronomical Society of the Pacific Issue: Volume 129:Number 973(2017) Page Start: Record Type: Journal Article View Content: Available online (eLD content is only available in our Reading Rooms) ↗