Similarly influential, and generally cited as proto-cyberpunk , is the Philip K. Dick novel "Do Androids Dream of Electric Sheep", first published in 1968. Presenting precisely the general feeling of dystopian post-economic-apocalyptic future as Gibson and Sterling later deliver, it examines ethical and moral problems with cybernetic, artificial intelligence in a way more "realist" than the Isaac Asimov "Robot" series that laid its philosophical foundation. Dick's protege and friend K. W. Jeter wrote a very dark and imaginative novel called "Dr. Adder" in 1972 that, Dick lamented, might have been more influential in the field had it been able to find a publisher at that time. It was not published until 1984, after which Jeter made it the first book in a trilogy, followed by "The Glass Hammer" (1985) and "Death Arms" (1987). Jeter wrote other standalone cyberpunk novels before going on to write three authorized sequels to "Do Androids Dream of electric sheep", named "Blade Runner 2: The Edge of Human" (1995), "Blade Runner 3: Replicant Night" (1996), and "Blade Runner 4: Eye and Talon".