A. Andersson. Improving Partial Rebuilding by Using Simple Balance Criteria,
In Proc. Workshop on Algorithms and Data Structures, Lecture Notes in Computer Science 382, Springer Verlag, pages 393--402, 1989.

Some new classes of balanced trees, defined by very simple balance criteria, are introduced. Those trees can be maintained by partial rebuilding at lower update cost than previously used weight-balanced trees. The used balance criteria also allow us to maintain a balanced tree without any balance information stored in the nodes.

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