The following publications are possibly variants of this publication:
- Improving Spanning Trees by Upgrading NodesSven Oliver Krumke, Madhav V. Marathe, Hartmut Noltemeier, R. Ravi, S. S. Ravi, Ravi Sundaram, Hans-Christoph Wirth. icalp 1997: 281-291
- Improving Spanning Trees by Upgrading NodesSven Oliver Krumke, Hartmut Noltemeier, Madhav V. Marathe, R. Ravi, S. S. Ravi, Ravi Sundaram, Hans-Christoph Wirth. TCS, 221(1-2):139-155, 1999. [doi]