Harvard Law Review good enough?
http://harvardlawreview.org/2015/03/on-the-meaning-of-natural-born-citizen/
While some constitutional issues are truly difficult, with framing-era sources either nonexistent or contradictory, here,
the relevant materials clearly indicate that a “natural born Citizen” means a citizen from birth with no need to go through naturalization proceedings. The Supreme Court has long recognized that two particularly useful sources in understanding constitutional terms are British common law3×3.
See Smith v. Alabama, 124 U.S. 465, 478 (1888). and enactments of the First Congress.4×4.
See Wisconsin v. Pelican Ins. Co., 127 U.S. 265, 297 (1888).Both confirm that the original meaning of the phrase “natural born Citizen” includes persons born abroad who are citizens from birth based on the citizenship of a parent.