GDNF family receptors in the embryonic and postnatal rat heart and reduced cholinergic innervation in mice hearts lacking Ret or GFRa2Hiltunen, J.O.; Laurikainen, A.; Airaksinen, Matti S.; Saarma, MartDevelopmental dynamics2000 / p. 28-39 https://pubmed.ncbi.nlm.nih.gov/10974669/

Neurturin mRNA expression suggests roles in trigeminal innervation of the first branchial arch in tooth formationLuukko, K.; Saarma, Mart; Thesleff, I.Developmental dynamics1998 / p. 207-219