[1]

John R. Stallings.

An extension theorem for Euler characteristics of groups.

*Geom. Dedicata*, 92:3-39, 2002.

Dedicated to John Stallings on the occasion of his 65th birthday.

[2]

Ian Chiswell.

Introduction to: ``An extension theorem for Euler characteristics

of groups'' [Geom. Dedicata **92** (2002), 3-39; MR 2003m:20068b] by

J. R. Stallings.

*Geom. Dedicata*, 92:1-2, 2002.

Dedicated to John Stallings on the occasion of his 65th birthday.

[3]

R. J. Zimmer, editor.

*Dedicated to John Stallings on the occasion of his 65th*

birthday.

Kluwer Academic Publishers Group, Dordrecht, 2002.

Geom. Dedicata **92** (2002).

[4]

John R. Stallings.

Surfaces mapping to wedges of spaces. A topological variant of the

Grushko-Neumann theorem.

In *Groups-Korea '98 (Pusan)*, pages 345-353. de Gruyter,

Berlin, 2000.

[5]

John R. Stallings.

Whitehead graphs on handlebodies.

In *Geometric group theory down under (Canberra, 1996)*, pages

317-330. de Gruyter, Berlin, 1999.