Fig8A [doi:10.1016/0925-4773(94)90078-7] Copyright: Reprinted with permission from Elsevier from Mech Dev 46(2): 87-100, Ruiz JC; Robertson EJ , The expression of the receptor-protein tyrosine kinase gene, eck, is highly restricted during early mouse development. Copyright 1994. [PMID:7918100]