Small pica is a traditional name for a metal type body size that translates to 11 points in the standardized typographic system. Before the point system standardized measurements, founders cast this size to be slightly smaller than a standard 12-point pica. It was a highly popular size for printing novels, legal documents, and reference books because it offered a comfortable balance of legibility and word count per page.
Set the main body text in small pica, but drop down to bourgeois for the footnotes.
The transition to the standardized point system made names like small pica obsolete, but 11-point text remains a standard default in digital word processors.