Grassmann’s Law (=GL) is generally regarded as a quintessential example of regular sound change, though dissimilation processes are generally said to be quite rare and sporadic. In the present paper, evidence is presented aiming to show “the phonetic prehistory” of Grassmann’s Law in Greek, namely a diachronic stage during which GL acts in all but regular fashion. In particular, especially in some dialectal areas, some forms retain the original diaspirate stem up until Classical epoque (V–IV c. BC). Moreover, the presence of an opposite process, that is the assimilation (generally regressive) between aspirated segments, is also documented. Both of these aspects seem to show a lexically constrained spread of such a change. Its relatively late regularity can be explained as a process implemented by phonological constraints, which intervene at some point in the linguistic change.

中文翻译：

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希腊格拉斯曼定律的“语音史前”

格拉斯曼定律（= GL）通常被认为是规则的声音变化的典型例子，尽管通常认为异化过程非常罕见且零星。在本文中，提供了旨在显示希腊格拉斯曼定律的“语音史前史”的证据，这是一个历时阶段，在此期间GL以常规方式行事。特别是，特别是在某些方言地区，某些形式保留了原始的旋流词干，直到古典时期（V–IV c。BC）。此外，还记录了相反过程的存在，即吸气段之间的同化（通常是渐进的）。这两个方面似乎都显示了这种变化的词汇限制。其相对较晚的规律性可以解释为语音限制所实现的过程，