Authority has two sections that seem to be a nod to Roadside Picnic: the "Maybe they called it a holiday retreat" passage on pg 37 recalls the passage from which the novella gets its name, and the image of military vehicles on pg 189 echoes an image from Stalker. Were these conscious nods? There were also echoes Lem's Solaris. Are these Eastern European writers touchstones for you? I'm looking forward to September!
You'd think they would be, right? I mean, I totally get why those touch points come up. If you write about expeditions into a strange place, chances are that's what's going to happen. But, no, "holiday retreat" is a reference to Nabokov's Bend Sinister, in which he uses the language of the travel brochure to refer to detention camps. The image of military vehicles came from seeing footage of a line of burning tanks during the first Gulf War.