Sturino, C.F., O’Neill, G., Lachance, N., Boyd, M., et al. (2007) Discovery of a potent and selective prostaglandin D2 receptor antagonist, [(3R)-4-(4-chloro-benzyl)-7-fluoro-5-(methylsulfonyl)-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl]- aceticacid (MK-0524). Journal of Medicinal Chemistry, 50, 794-806.