Where is the lambda sensor on a saxo vtr?

mk1 VTR has one it is located under the car in the down pipe.

mk2 VTR has two, one located on manifold - the end of the cable running through the heat-shield at the front of the engine (pre-Cat converter) and one after the Cat converter where the down pipe meets the centre section.

Recommend some heat present in the exhaust pipes and lots of brute force / perseverance / ignorance to remove any of these sensors!!!