# Article

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Keywords:
mode; differential groupoid; lattice of subquasivarieties; $\Cal Q$-universal quasivariety
Summary:
The main result of Romanowska A., Roszkowska B., {\it On some groupoid modes\/}, Demonstratio Math. {\bf 20} (1987), no. 1--2, 277--290, provides us with an explicit description of the lattice of varieties of differential groupoids. In the present article, we show that this variety is $\Cal Q$-universal, which means that there is no convenient explicit description for the lattice of quasivarieties of differential groupoids. We also find an example of a subvariety of differential groupoids with a finite number of subquasivarieties.
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