I don't think is what the person was looking in terms of statistics on bf,
but here are two interesting references:

Salmon, Marylynn  1994
        "The Cultural Significance of Breastfeeding and Infant Care in Early
Modern England and America," Journal of Social History, 28(2):247-269.


Treckel, Paula A.  1989
        "Breastfeeding and Maternal Sexuality in Colonial America," Journal
of Interdisciplinary History, 20(1):25-51.

Kathy Dettwyler
Queen of References