I. Foundations of the theory
Linear Differential Transformations of the Second Order, GDML_Books, (1971), p. [1] / Harvested from
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@inbook{401669,
     title = {I. Foundations of the theory},
     booktitle = {Linear Differential Transformations of the Second Order},
     series = {GDML\_Books},
     publisher = {The English Universities Press, Ltd.},
     address = {London},
     year = {1971},
     pages = {[1]-[1]},
     url = {http://dml.mathdoc.fr/item/401669}
}

 (éd.). I. Foundations of the theory, dans Linear Differential Transformations of the Second Order, GDML_Books,  (1971), p. [1]. http://gdmltest.u-ga.fr/item/401669/