@unpublished{Peirce1903 [c.],
author = "Charles S. Peirce",
title = "{Topics. Chapter I. Singular Systems. MS [R] S18}",
year = 1903 [c.],
keywords = "System, Chorisy",
language = "English",
note = "From the Commens Bibliography | \url{http://www.commens.org/bibliography/manuscript/peirce-charles-s-1903-c-topics-chapter-i-singular-systems-ms-r-s18} *** {Notes: Dating based on Christian Kloesel's dating of MS [R] 151
}"
}
