The internal "sandhi" rules are more intricate and account for the root and the canonical structure of the Sanskrit word. These rules anticipate what are now known as the Bartholomae's law and Grassmann's law. For example, states Jamison, the "voiceless, voiced, and voiced aspirated obstruents of a positional series regularly alternate with each other (p ≈ b ≈ bʰ; t ≈ d ≈ dʰ, etc.; note, however, c ≈ j ≈ h), such that, for example, a morpheme with an underlying voiced aspirate final may show alternants with all three stops under differing internal sandhi conditions". The velar series (k, g, gʰ) alternate with the palatal series (c, j, h), while the structural position of the palatal series is modified into a retroflex cluster when followed by dental. This rule create two morphophonemically distinct series from a single palatal series.