Aprea, M.C. et al. 2017. Methodology to define biological reference values in the environmental and occupational fields: the contribution of the Italian Society for Reference Values (SIVR). La Medicina del Lavoro | Work, Environment and Health. 108, 2 (Apr. 2017), 138–148. DOI:https://doi.org/10.23749/mdl.v108i2.5574.