Source: Web Gallery of Art

Master of the St. Bartholomew Altar
Altarpiece of St. Thomas (detail of center panel)

1501
Oak, 143 x 106 cm (central panel), 143 x 47 cm (each wing)
Wallraf-Richartz Museum, Cologne
Gift of Peter Rinck to the Carthusian church of St. Barbara in Cologne.

The female saint on the left could be St. Margaret.

Also available:

More of St. Thomas
More of St. Jerome
More of St. Martha