I just picked up that Julian Tudor Hart died 1st July this year. I looked him up after coming across a reference to his research in an article by 3 local doctors here in Norway concerned with the weakening of the GP system: his work clearly had an international reach. Here are some obituaries.

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31660-X/fulltext

https://www.theguardian.com/society/2018/jul/12/julian-tudor-hart-obituary

https://www.bmj.com/content/362/bmj.k3052

https://keepournhspublic.com/in-memory/julian-tudor-hart-has-died-his-principles-live-on/