The theory of R. Crowell on derived modules is approached within the theory of non-commutative differential modules. We also seek analogies to the theory of cotangent complex from differentials in the commutative ring setting. Finally, we give examples motivated from the theory of Galois coverings of curves.

中文翻译：

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亚历山大模块的非交换差分模块方法

R. Crowell关于导出模块的理论是在非交换微分模块的理论之内进行的。我们还从可交换环设置中的微分中寻求与余切复数理论的类比。最后，我们给出了基于伽罗瓦曲线覆盖理论的例子。