I finally found the 2 references I was looking for regarding allergic
reaction to hydrolyzed protein in formula.

Saylor, John  and Sami L. Bahana "Anaphylaxis to Casein Hydrolysate Formula".
Journal of Pediatrics. 1991. vol 118: 71-74.

Ellis, Mark, et al. "Anaphylaxis after ingeestion of a recentyly introduced
hydrolyzed whey protein formula". Journal of Pediatrics. 1991. vol 118:74-77.

Martha Brower RD LD IBCLC
Queen of unfiled articles piled to the sky