We present HST/WFPC2 observations ( F555W , F814W ) and ATCA high resolution H i maps of three gas-rich dwarf galaxies in the Centaurus A group discovered in two blind 21-cm surveys ( HIPASS , HIDEEP ) .
We compare their individual properties and discuss their star formation history .
Although we can not constrain the age of the oldest population from the diagrams very well , the presence of an extended population of red giant stars suggests that these systems were not formed recently .
The presence of asymptotic giant branch ( AGB ) stars in two out of three dwarfs , sets a lower limit on the age of about 6 Gyr .