These on-line essays are well-written and serious studies of the film noir genre:
No Place for a Woman: The Family in Film Noir by John Blaser
Film Noir’s Progressive Portrayal of Women by John Blaser
Film Noir & the Hard-Boiled Detective Hero by John Blaser
The Outer Limits of Film Noir by John Blaser
Nietzsche and the Meaning of Noir by Mark Conard
Dark Art by Chris Fujiwara
An Introduction to Neo-Noir by Lee Horsley
The Urban Landscape of Marxist Noir by Alan Wald
European Film Noir by K H Brown
Film Noir: Fear In The City by Bruce Hodsdon
Film Noir and the German-Hollywood Connection by Hyde Flippo
Film Noir as Deferred Action by Steffen Hantke
Rerunning Film Noir by Richard Schickel
Shades Among Shadows: The Murder Mystery, Film Noir, and Poetry by David Lehman
Lost in the Dark: The Elusive Film Noir by Patrick Ellis
The Cinematic Flaneur:
Manifestations of modernity in the female protagonist of 1940s film noir
by Dr Petra Désirée Nolan
Film Noir: You sure you don’t see what you hear? by Raffaele Caputo