One common method for dispensing LSD is to drop a small amount of a solution containing LSD onto a piece of blotting paper, which may or may not have artwork on it.

That's about as definitive as I'm willing to get. Certainly not every piece of blottting paper has LSD on it, and it's certainly possible for someone to draw pictures on blotting paper which does not have LSD stamps Online on it.

(Another method for distributing LSD was to use an eyedropper to place a drop of LSD solution on a sugar cube. Obviously not every sugar cube has LSD in it, though!)