Functional and comparative analysis of two distinct ecdysteroid-responsive gene expression constructs in Drosophila S2 cells4409, Poels, J, Martinez A.J., Suner M.M., De Loof A., Dunbar S.J., and J. Broeck Vanden , Insect Biochem.Mol.Biol., 0/5/2004, Volume 34, Issue 5, Number 458, p.451 - 458, (2004)