Linking forms of amphichiral knots, with Stefan Friedl and Allison N. Miller. A preprint that we wrote before discovering that the main corollary had been proven by Goeritz in 1933. It is somewhat surprising that this method of detecting chirality does not appear in modern knot theory textbooks.
Lecture notes on the disc embedding theorem for topological 4-manifolds based on lectures by Michael Freedman in January and February 2013 for the Max Planck Institute semester on 4-manifolds, typed up by members of the Bonn audience (mostly by Stefan Behrens).
A survey of the work of Cochran-Orr-Teichner on knot concordance, which was essentially chapter 7 of my thesis.
Lecture notes on Slice Knots based on a course given by Peter Teichner which Julia Collins and I typed up at the beginning of our PhD studies.
A short note containing the statement of Alexander duality in a disc.
Some notes on constructing duality chain equivalences for some simple manifolds, in the sense that the word problem is easy for their fundamental groups.
An expository note on the basic operation which removes intersections of immersed surfaces in 4-manifolds.
The Manifold Atlas page on the Blanchfield form.
Notes on the Borsuk-Ulam Theorem which give a proof using chain complexes, and on which I based a Geometry Club talk at Edinburgh.
Problem list from the problem session at the conference Synchronisation of smooth and topological 4-manifolds at Banff, February 2016.