Going by the Beverol sponsorship everywhere, European Escort, Datsun 510's & Z I'm going to guess at Zandvoort, Touring Car Races sometime mid 70's.
Do you have the answer or wanting to know?
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.