# Bondy, J. Adrian

## Cyclic spanning subdigraph with small cyclomatic number ★★

Author(s): Bondy

**Conjecture**Let be a digraph all of whose strong components are nontrivial. Then contains a cyclic spanning subdigraph with cyclomatic number at most .

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## Switching reconstruction of digraphs ★★

**Question**Are there any switching-nonreconstructible digraphs on twelve or more vertices?

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