Mathematical proof - Wikipedia

When is it acceptable in a rigorous mathematical proof to cite a result from folklore without supplying your own demonstration of that truth? For example, ''n choose m' is always an integer

Mathematical Thoughts: Group Theory in SageMath by Khyati Sharma, SNU, Greater Noida

Theorem Proving in Mathematics

CS2214, Fall 2020: Discrete Structures for Computing, Marc Moreno-Maza

zun maths

What's a mathematical statement that you can prove using only one picture? - Quora

Mathematical proof - Wikipedia

Is it true that scientific theories can never be proven, only disproven? - Quora

2 + 2 = 5 - Wikipedia

Books: John Conway