NEC Legal? 30A Breaker with 12AWG and 20A Receptacle

[Always4]

Based on principal:
15A- 14AWG
20A- 12AWG
30A- 10AWG

Is there a specific code reference that prohibits 12AWG NM Cable and 20A receptacles on a Single Pole 30A breaker?

 

[infinity]

There are several NEC sections that would prohibit this. Here is two: {Table 210.21(B)(3)} {240.4(D)(5)}

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