Edwin was interested in adaptive distances: Edwin Diday, Gerard Govaert: Automatic Classification with Adaptive Intervals.[Classification automatique avec distances adaptatives.] January 1977 ResearchGate
In 1981 I published a paper: Batagelj, V. Note on ultrametric hierarchical clustering algorithms. Psychometrika 46, 351–352 (1981). DOI, Springer
Edwin wrote me a letter in 1981 or 1982. I visited him at INRIA. He gave me his recent book on “nuées dynamiques” in two volumes (I can read French). He applied my result in:
Edwin Diday: Inversions en classification hiérarchique : application à la construction adaptative d'indices d'agrégation. Revue de Statistique Appliquée (1983) Volume: 31, Issue: 1, page 45-62 EDML
and
E Diday, J.V Moreau: Learning hierarchical clustering from examples — application to the adaptive construction of dissimilarity indices, Pattern Recognition Letters, Volume 2, Issue 6, 1984, Pages 365-378, ISSN 0167-8655, DOI, paper
In the eighties, we met at several conferences. Researchers from the field of multivariate analysis established a new society IFCS.
I became interested in SDA during a discussion with Edwin after his presentation on SDA (invited talk?), if I remember well, at the COMPSTAT conference in Dubrovnik in 1990.
With Simona, we started to work on the clustering of symbolic objects described with “distributions”. Edwin invited us to join the Esprit project ISO3D, Datana.
Some recent photos on my Facebook
and additional on USB,