Inferno is a 1980 Italian horror film directed by Dario Argento. It is 2nd in the Three Mothers trilogy. There's a fountain pen about 2 and a half minutes in.
I'm not seeing the video, which should be embedded below, but it's available online at this link. [it was available but has been removed] There is a trailer here:
Moria gives it 4 stars. Images Journal calls it "a film of sparse plot and indelible imagery." Slant Magazine details the plot. MSN has an overview.