**DIPS 1/97**[tex source, PostScript, dvi]-
**Title:**SOME LOCAL PROPERTIES OF B\"ACKLUND TRANSFORMATIONS**Author:**Michal MARVANFor B\"acklund transformations, treated as relations in the category of diffieties, local conditions of effectivity and normality are introduced, having implications for the solution generating properties. We check them for the pKdV, the sine-Gordon, and the Tzitz\'eica equation.

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