A Slavonian/Slovenian biographical history of configurations
This talk will discuss configurations and their history from a Slavonian, from a Slovenian, and from the author's point of view. Configurations are linear regular uniform hypergraphs, but investigated in a geometric language since 1876. Slavonia is a region in the east of Croatia, not to mix up with Slovenia, an independent state since 1991/1992. There are two recent books on configurations by the Slavonian Branko Gr\"unbaum, born in Osijek in 1929 "Configurations of points and lines'', and by the Slovenian Toma\v z Pisanski, born in Ljubljana in 1949 "Configurations .....''.
These configurations will be displayed in connection with the above mentioned books, with the author's own research and with the history of the last 30 years, seen through combinatorial conferences, e.g. 1988 in Ravello, 1991 in Bled, and further events in Slovenia.
This talk is motivated by publications of the Slavonian scholar Milutin Milankovi\'c (1879- 1958) such as M.M.: Durch ferne Welten und Zeiten. Briefe einesWeltallbummlers, Leipzig (1936) (or the Serbian work of 1928), and M.M.: Zgodovina astronomije od njenih prvih začetkov do leta 1727, Ljubljana (1951).
In these two works M.M. mixes reports about astronomy, its history with biographical aspects of his own life.