Evaluation of the immune benefits of two probiotic strains Bifidobacterium animalis ssp. lactis, BB-12® and Lactobacillus paracasei ssp. paracasei, L. casei 431® in an influenza vaccination model: a randomised, double-blind, placebo-controlled study

PubMed: 21899798

Probiotic effects on cold and influenza-like symptom incidence and duration in children

PubMed: 19651563