Mathematician J.E. Littlewood once wrote a paper for the French journal Comptes Rendus. A Prof. M. Riesz did the translation, and at the end Littlewood found three footnotes:

I am greatly indebted to Prof. Riesz for translating the present paper.

I am indebted to Prof. Riesz for translating the preceding footnote.

I am indebted to Prof. Riesz for translating the preceding footnote.

Littlewood notes that this could have gone on indefinitely but “I stop legitimately at number 3: however little French I know I am capable of copying a French sentence.”