Michael W. Botsko. An Elementary Proof of Lebesgue's Differentiation Theorem. The American Mathematical Monthly, 110(9):834-838, 2003. [doi]
@article{Botsko03, title = {An Elementary Proof of Lebesgue's Differentiation Theorem}, author = {Michael W. Botsko}, year = {2003}, url = {http://www.jstor.org/stable/3647803}, researchr = {https://researchr.org/publication/Botsko03}, cites = {0}, citedby = {0}, journal = {The American Mathematical Monthly}, volume = {110}, number = {9}, pages = {834-838}, }