strel_bol function for creating a head model

[Brian Roach]

FT users,

This tutorial
(http://www2.ru.nl/fcdonders/fieldtrip/doku.php?id=fieldtrip:documentation:create_bem_headmodel_for_eeg)
calls a function "strel_bol", which I do not have in my matlab
library.  Does anyone have this function?  Is it from one of the toolboxes,
FieldTrip, or some other location?  I have just downloaded the latest F.T.
version and cannot find this function.

thanks,
Brian