Hey, is it possible to get a longer arrow, and one with a solid head, in the following? +++ \usepackage{amsmath} \[ R_i' \overset{S_{i+1}'}\longrightarrow R_{i+1}' \] +++ Kind regards, James No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.472 / Virus Database: 269.8.9/832 - Release Date: 04/06/2007 18:43