1. http://history.nih.gov/exhibits/thinblueline/timeline.html#1970
2. Plotz, C.M. and Singer, J.M. (1956) The latex fixation test. Application to the serologic diagnosis of rheumatoid arthritis. Am. J. Med. 21(6):888–892.
3. Berson, S.A. and Yalow, R.S. (1959) Quantitative aspects of the reaction between insulin and insulin binding antibody. J. Clin. Invest. 38:1996–2016.
4. Campbell, R.L., Wagner, D.B. and O’Connel, J.P. (1987) Solid-phase assay with visual readout, US Pat. 4,703,017.
5. Rosenstein, R.W. and Bloomster, T.G. (1989) Solid-phase assay employing capillary flow, US Pat. 4,855,240.