In the list, "line -*n*" means *n* lines up from the bottom.
I am grateful to Bruce Sagan, Jonathan Hall, and their students, and to
Jacobus Swarts, for many of the items on this list.

- page 31, line -3: "Exercise 12" should be "Exercise 14"
- page 31, line -2: "Exercise 13" should be "Exercise 15"
- page 44, line -2: "
*k*is odd" should be "*n*is odd" - page 45, line 12: "Section 3.11" should be "Section 3.12"
- page 61, line -4: "2
*n*-2" should be "2*n*" - page 62, line -5: This double exponential is underfined as a formal power series
- page 72, Ex 20(a): "1-
*t*^{2}" should be "1-*t*" - page 81, line 7: "than" should be "that"
- page 97-98: There is no Exercise 2
- page 98, Exercise 3(c): The sequence should be
(
*x*_{0}, ...,*x*_{n-1}), not (*x*_{1}, ...,*x*_{n}); and*i*should run from 0 to*n*-2 instead of 1 to*n*-1. (Spotted by Nik Ruskuc.) - page 102, line 3: "(
*n*-|*A*|!)" should be "(*n*-|*A*|)!" - Page 103, line -13:
*r*>=_{i}*k*should be_{j}*r*<=_{i}*k*. (Spotted by Nik Ruskuc.)_{j} - Page 104, line -9: replace "suppse" by "suppose".
- Page 105, paragraph after Remark 2: The sets in F should be
{
*x*} union*U*and {*x*} union*V*, and their complements {*y*} union*V*and {*y*} union*U*. (Spotted by Nik Ruskuc.) - Page 107: Bruce Sagan says: "It was brought to my attention in class
today that in order for Theorem 8.1.2 to be true for
*n*=3 you need to allow*n*=*m*, while on page 107 you insist that*n*>*m*. It's a minor point, but there is nothing wrong with allowing*n*=*m*=l." - page 111: note that three of the lines of the STS are not shown in the figure
- Page 112: to get a subsystem of order 7, we require
*w*> 1 rather than*w*> 0. (Spotted by Jacobus Swarts) - page 131, line 4: "puropse" should be "purpose"
- page 131, definition of projective plane: second B should be X. (Spotted by Jacobus Swarts)
- page 134, second last paragraph of the proof of (9.5.6):
*L'*should be*L''*twice ("...parallel to the same line*L''*are ..." and "... are disjoint from*L''*, which ..."). (Spotted by Dudley Stark.) - page 137, line 2:
*W=v*should be*W*+*v* - page 137, line -13: delete opening parenthesis
- page 137, line -5:
*r*-1 should be*r*+1 in two places - page 137, line -2:
*t*+1 should be*t*-1 - page 138: The use of [*,*,*] for [
*x,y,z*] and [*a,b,c*] is confusing. - page 141, line -13: "6
^{th}" should be "*i*^{th}" - page 141, line -3: "Fact 4" should be "Fact 3"
- page 145, line -5: The
*degree*of a net is defined to be the number of parallel classes. - page 192, 8th line of proof: represesnted -> represented (Spotted by Jacobus Swarts)
- page 198, Proposition 12.6.1(b): the
*n*in the index of the last lattice in the list should be*r*. (Spotted by Jacobus Swarts) - page 200, line 10: "1 <=
*i*<=*n*" should be "1 <=*k*<=*n*" - page 202, line 1: One also needs to check that this
*mu*is in*I*(*P*_{1}x ... x*P*) (which is easy, but should be noted)._{k} - page 202, line -11: "precisely" should be "dually"
- page 203, Exchange axiom:
*z*should not be in*Y*. (Spotted by Yatin Nandwani). - page 260, line after displayed equation: inequality -> equality. (Spotted by Jacobus Swarts)
- page 261, line 1: mod 3 -> mod 2. (Spotted by Jacobus Swarts)
- page 261, line 13: "16.1.2" should be "16.1.3"
- page 263, line -6: "root" should be "double root"
- page 268: "Haramard" should be "Hadamard" (spotted by Colton Magnant)
- page 269, Exercise 1: "
*v*+1 divides*b*(*k*+1)" should read "*k*+1 divides*b*(*v*+1)". (Spotted by Ron Gould) - page 319, line 8: "specail" should be "special"
- page 320, line -9: "exampes" should be "examples"
- page 353, projective plane entry: "102" should be "103"

Peter J. Cameron

`p.j.cameron(at)qmul.ac.uk
19 October 2005.
`