A letter written by Mill in 1854 suggests the attribution of credit goes both ways for her and John Stuart Mill; "I shall never be satisfied unless you allow our best book, the book which is to come, to have our two names on the title page. It ought to be so with everything I publish, for the better half of it all is yours". There is speculation that this indicates some reluctance on her part, even after her husband's death. Certainly, he was very reluctant that her name be linked with Mill's in public during his lifetime, even in a suggested dedication to "Principles of Political Economy" in 1848. However, this letter adds to the evidence from Mill's "Autobiography" and textual analysis of their pieces, that the two worked as a pair for much of their work.