If you make use of data from the Radio Reference Frame Image Database in any publication, please add the following acknowledgement:

This research has made use of the United States Naval Observatory (USNO) Radio Reference Frame Image Database (RRFID).

If the RRFID data for a particular epoch has already been published by us, please cite the published reference instead. We have published VLBA data from epochs 1994JUL08(1), 1995APR12(2), 1995OCT12(2), 1997JAN10(3), and 1997JAN11(3) in ApJS and data from the Southern Hemisphere LBA campaign in AJ; the references are as follows...

(1) Fey, A. L., Clegg, A. W., & Fomalont, E. B. 1996, ApJS, 105, 299
(2) Fey, A. L. & Charlot, P. 1997, ApJS, 111, 95
(3) Fey, A. L. & Charlot, P. 2000, ApJS, 128, 17
(4) Ojha, R., Fey, A. L., et al. 2004, AJ, 127, 3609