- FAA - Site Listing of Legacy Radars as of 23 Dec 2016.
- U.S. DoT - Recommendation on Transition from Primary/Secondary Radar to Secondary-Only Radar Capability 1994.
- FAA - Three Level Weather For ARTCC Displays - Project Implementation Plan, FAA Order 7110.14A, 14 Feb 1990.
- FAA - SSR/DMTI Modification - Project Implementation Plan, FAA Order 6340.20, 6 Jul 1988.