Hi, Subject line says it all really. Tried ${\bf \mu}$ $\textbf{\mu}$ $\tmmathbf{\mu}$ $\mathbf{\mu}$ So far I've view the output with xdvi and xpdf. I'm using pdfeTeX Version 3.141592-1.21a-2.2 (Web2C 7.5.4) on a Linux box. Anyone any ideas? Thanks,David.