title: Erratum to: Biochemistry of primary headaches: role of tyrosine and tryptophan metabolism.
authors.affiliation: Research & Innovation (R&I), Padua, Italy.
authors.forename: G
authors.initials: G
authors.lastname: D'Andrea
authors.affiliation: Neurology Department, Headache Center, IRCCS Institute of Neurological Sciences, Bologna, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Cevoli
authors.affiliation: Research & Innovation (R&I), Padua, Italy. colavito@researchinnovation.com.
authors.forename: D
authors.initials: D
authors.lastname: Colavito
authors.affiliation: Research & Innovation (R&I), Padua, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Leon