Here, for the record, are the other papers in the cache I found this week. Apart from preprints of papers which were published, there are five typescripts and a number of handwritten pages. The unpublished typescripts are:

- Rosemary A. Bailey and Peter J. Cameron,
*The eigenvalues of averaged symmetric matrices*. [Our first joint paper, rejected and never published. The paper sets the problem of finding the eigenspaces of the*n*×*n*matrix obtained by averaging the images of a real symmetric matrix under a transitive group acting on {1,…,*n*}, and why statisticians want to do this.] - Peter J. Cameron,
*Yet another generalisation of Fisher’s inequality*. [Proved in response to a question from one of my first PhD students at Queen Mary, Mark Whelan. An*m*-part*t*-design on a set*X*of points is a collection of functions from*X*to {1,…,*m*} such that the inverse images of each point in all functions have the same size, and the number of functions taking prescribed values on*t*distinct points depend only on the prescribed values and not on the chosen points. For*m*= 2, this is equivalent to a complementary pair of*t*-designs. I show that an*m*-part 2-design has at least (*m*−1)*v*functions, where*v*is the number of points.] - Peter J. Cameron,
*Locally projective spaces and the transitivity of parallelism*. Submitted to a journal, possibly*Math. Z.*, in 1976; rejected, then abandoned. [A study of geometries with the property that, if three hyperplanes have the property that two of the three intersections are codimension-2 subspaces, then the third is empty or codimension-2.] - Peter J. Cameron,
*Paired suborbits*. [Sims showed that paired subconstituents in a finite transitive permutation group must have a common no-trivial quotient; in my thesis I used his method to prove other results of this sort, and this note extends the ideas further.] - Peter J. Cameron,
*Automorphism groups of parallelisms*. [These are parallelisms of the design of all*t*-subsets of an*n*-set, where*t*divides*n*. Some of this went into my book on parallelisms.]

There are also some handwritten papers:

- Three things I wrote as an undergraduate: one takes the set of unordered
*n*-tuples over some mathematical structure (ordered set, field, metric space) and explores giving it a related structure; one considers the set of 2×2 real matrices commuting with a given matrix and attempts to mimic the structure of the complex numbers; the third takes the set {1,2,…,*mn*}, partitions it into*m*sets of size*n*, takes the product of the numbers in each set and adds these products, and asks: what is the minimum value? - Three different constructions starting from a Hadamard matrix of order
*n*and producing symmetric Hadamard matrices of order*n*^{2}with constant diagonal and constant row and column sums. - A generalisation of the outer automorphism of M
_{12}: take a pair of 3-designs, in each of which the complement of a block is a block, and there are correspondences between pairs of points in one design and complementary pairs of blocks in the other. - Subsets of projective planes having a constant size intersection with every secant.
- Yet more generalisations of Fisher’s inequality, some of which got into my BCC papers in 1973 and 1977. One document considers designs in vector spaces; the other, designs in association schemes.
- Some characterisations of 2-arc transitive graphs (if they have enough quadrangles, they are known: this grew out of my thesis, but unlike there, it did not assume vertex-primitivity.
- Relations between paired subconstituents of transitive permutation groups. (Sims showed that they must have a common no-trivial quotient; in my thesis I used his method to prove other results of this sort, and this note extends the ideas further.)
- A paper with Peter Neumann characterising the permutation groups which are 3/2-transitive on the
*k*-subsets of the domain, for some*k*: the groups S_{7}and A_{7}are the only examples.

The most interesting to me are the undergraduate pieces, since it might seem as if a lot of the mathematics I did grew from considering the structure of the set of *k*-subsets of an *n*-set.

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