Who drew this, and from what.

Every pillar on this site is a reading of someone else’s talk. The structure, the examples, and every external figure quoted anywhere here come from these, and each figure is attributed on the sheet to the person who gave it — no number is carried from one talk to a sheet credited to another. The synthesis, the diagrams, and any mistakes are mine.

Most feed a whole pillar. Where a talk goes deep on a single primitive it is credited on that sheet instead, and where one talk is large enough to raise a run of sheets it is credited on all of them — marked below with the sheets it stands under.

Sources read since — reports and talks that are examined here rather than built into a pillar — are kept in the reading room.