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Linear Differential Transformations of the Second Order. The English University Press, London 1971.
MR 0463539
[2] Laitochová J.:
On a Canonical Two-dimensional Space of Continuous Functions. ACTA UPO Vol.91, 1988, in print.
MR 1039887 |
Zbl 0692.46019
[3] Laitochová J.:
On Two-dimensional Linear Spaces of Continuous Functions of the Same Character. ACTA UPO Vol.94, 1989, in print.
MR 1053733 |
Zbl 0704.34044