The following papers are available for downloading:

A User's Guide to the BLACS v1.1,
Jack J. Dongarra and R. Clint Whaley
The BLACS v1.1 User's Guide.
Installing and Testing the BLACS,
R. Clint Whaley
Anyone wishing to test a BLACS version or install the BLACS should read this guide.
Outstanding Issues in the MPIBLACS,
R. Clint Whaley
A discussion of the outstanding issues in the alpha release of the MPIBLACS.
Some Plebian Extensions to MPI,
R. Clint Whaley
A small note on some BLACS-related MPI issues.
Quick reference guide for the BLACS' Fortran 77 interface.,
Quick reference guide for the BLACS' C interface.,

NOTE: all of this stuff is for the old version of the BLACS ...

Basic Linear Algebra Communication Subprograms: Analysis and Implementation Across Multiple Parallel Architectures,
R. Clint Whaley,
LAPACK Working Note 73, technical report, University of Tennessee, 1994.
Two Dimensional Basic Linear Algebra Communication Subprograms,
Jack Dongarra and Robert van de Geijn,
LAPACK Working Note 37, technical report, University of Tennessee, 1991.

The following codes are available for downloading:

The BLACS tester for all versions of the BLACS.
A tar file containing the BLACS tester.
MPIBLACS.
A tar file containing the BLACS written on top of MPI. If you download this BLACS version, be sure to read the following papers:
Installing and Testing the BLACS,
Outstanding Issues in the MPIBLACS,
Some Plebian Extensions to MPI,
MPLBLACS.
A tar file containing the BLACS (written on top of MPL) for IBM's SP series.
NXBLACS.
A tar file containing the BLACS (written on top of NX) for Intel's supercomputer series (ipsc2, i860, DELTA and PARAGON).
PVMBLACS.
A tar file containing the BLACS written on top of PVM.