Immune responses to bovine respiratory syncytial virus (BRSV) following use of an inactivated BRSV-PI3-Mannheimia haemolytica vaccine and a modified live BRSV-BVDV vaccine., Kerkhofs, Pierre, Tignon Marylène, Petry H, Mawhinney I, and Sustronck B , Vet J, 2004 Mar, Volume 167, Issue 2, p.208-10, (2004)