Redoing the lawn
 

The soil of my plot is 100% clay,apart for one foot of meadow skim soil deposited on top 35 years ago.Drought is a constant feature (I live in northern Italy),temperature 30 deg in the summer,african size weeds,part of the lawn is in direct sunshine,part under the shadow of a neighboring oak wood.I decided to re-do the lawn,but I have no idea which grass to go for,given the circumstances.I've read that Zoysia and other grasses in the same group might work better in these conditions,but I have no idea.I need advice.Please give me the botanical names of the grasses,so that I can try and find the seeds locally.Thanks.
Carlo