9 Relations between first phases of two differential equations (q), (Q)
Linear Differential Transformations of the Second Order, GDML_Books, (1971), p. [94]-101 / Harvested from
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@inbook{401678,
     title = {9 Relations between first phases of two differential equations (q), (Q)},
     booktitle = {Linear Differential Transformations of the Second Order},
     series = {GDML\_Books},
     publisher = {The English Universities Press, Ltd.},
     address = {London},
     year = {1971},
     pages = {[94]-101},
     url = {http://dml.mathdoc.fr/item/401678}
}

 (éd.). 9 Relations between first phases of two differential equations (q), (Q), dans Linear Differential Transformations of the Second Order, GDML_Books,  (1971), pp. [94]-101. http://gdmltest.u-ga.fr/item/401678/