In one example, a print job is received. The print job includes a first plot to be printed on a first side of a media, and a second plot to be printed on a second side of the media in registration with the first plot. The first plot and a fiducial mark are caused to print on the first side, the fiducial mark being a known distance from the first plot and including an identifier for the second plot. In response to detecting the identifier via a sensor and measuring a distance to the fiducial mark to discern a reference for printing the second plot, the second plot is caused to print on the second side in registration with the first plot.