@article{CG_2011___56_69_0,
     author = {Kula, J\'an and St\v{r}{\'\i}\v{z}, Pavel},
     title = {Preface},
     journal = {Cahiers GUTenberg},
     pages = {69--69},
     publisher = {Association GUTenberg},
     number = {56},
     year = {2011},
     language = {en},
     url = {http://archive.numdam.org/item/CG_2011___56_69_0/}
}