Yossi Shiloach . Edge-disjoint branching in directed multigraphs. Adi Shamir . A note on vector grammars. A note on bottom-up pyramid acceptors.
Reference counting can manage the circular environments of mutual recursion.
Alberto Bertoni , Giancarlo Mauri , and Mauro Torelli . Three efficient algorithms for counting problems. Notes on the derivation of asymptotic expressions from summations. Batch scheduling from short lists. Deadline scheduling of tasks with ready times and resource constraints.