Figure 4F. Copyright: This image is from Basson MA; Echevarria D; Petersen Ahn C; Sudarov A; Joyner AL; Mason IJ; Martinez S; Martin GR, "Specific regions within the embryonic midbrain and cerebellum require different levels of FGF signaling during development." Development 2008; 135: 889-98 [doi:10.1242/dev.011569] and is displayed with the permission of The Company of Biologist Limited who owns the Copyright. [PMID:18216176]