I think it’s Euclid. (Click the “Type Design” tab and then click “List of fonts” on the bottom. You’d see Euclid on the third line from the top.)
Though the retail version is a little bit different. (Have a look at the y and the s.)

Brilliant, thank you so much. Yes strange that the retail version has such subtle differences. A shame because I prefer the "original" y and s! Ahh I was hoping there was more than 1 weight available but oh well! Thanks again for your quick reply!