The notion of homotopy in the category of morphisms introduced by Górniewicz and Granas is proved to be equivalence relation which was not clear for years. Some simple properties are proved and a coincidence point index is described.

中文翻译：

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关于态射同构和可容许映射

由Górniewicz和Granas引入的态射范畴中的同伦概念被证明是等价关系，这种关系多年来一直不清楚。证明了一些简单的性质并描述了重合点索引。