I have many things to remember about my friend and guru Rene DAVID. I learnt a lot about Petri nets and Grafcet from him. My PhD work used Petri nets. 
I also managed to get him to India, Hyderabad, to deliver a one-week course on Petri Nets and Grafcet (along with Hassane Alla), in Dec. 1991. This course was conducted on behalf of IEEE Hyderabad, and was sponsored by the French Embassy in India.
He also gifted me 
his book on this subject (which was originaly written in French. I helped him in its translation to English). I cherish this book, till today.
He visited my home, celebrated Christmas with us, inspected and approved the accessible house I had built with the inspiration he had given me in Grenoble, France. It was a memorable experience for my children and me.
Rene might have left us, but his books and his memories will always be with us.
See also : Rene DAVID (RIP)
It is a sad duty for me to announce the death of my long-time friend and guru René DAVID (1939–2022). I met him first in 1977 when I went to Grenoble for my Doctorate. I had a lot of close interactions with him during my stay there. He was a remarkable scientist, sportsperson, and above all, a highly-cultured gentleman. He inspired me to 
And I have a lot of literature (some translated by me) on IRIS, the device to help blind persons practice archery.