@article{701857,
     title = {On certain quantities in Fredholm operator theory and Mil'man's isometry spectrum},
     booktitle = {Proceedings of the 13th Winter School on Abstract Analysis},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {1985},
     pages = {[17]-24},
     zbl = {0659.47014},
     url = {http://dml.mathdoc.fr/item/701857}
}

Beucher, O. J. On certain quantities in Fredholm operator theory and Mil'man's isometry spectrum, dans Proceedings of the 13th Winter School on Abstract Analysis, GDML_Books,  (1985), pp. [17]-24. http://gdmltest.u-ga.fr/item/701857/