@unpublished{Peirce1903,
author = "Charles S. Peirce",
title = "{CSP's Lowell Lectures of 1903. Introduction to Lecture 5. MS [R] 468}",
year = 1903,
abstract = "{Robin Catalogue:
A. MS., notebook, n.p., December 4, 1903, pp. 1-9.
Gamma part of graphs continued (but quickly abandoned). Graphs of logical principles. Beta part.
}",
keywords = "Gamma Graph, Principle of Contradiction, Principle of Excluded Middle, Continuous Line",
language = "English",
note = "From the Commens Bibliography | \url{http://www.commens.org/bibliography/manuscript/peirce-charles-s-1903-csps-lowell-lectures-1903-introduction-lecture-5-ms-r}"
}