TY  - RPRT
TI  - Orchestrating ontogenesis: variations on a theme by sonic hedgehog.
AU  - Philip W Ingham
AU  - Marysia Placzek
PY  - 2006
DO  - 10.1038/nrg1969
UR  - https://pubmed.ncbi.nlm.nih.gov/17047684/
ID  - 17047684
ER  -