Stewart, I. A. (1991). Deciding whether a planar graph has a cubic subgraph is NP-complete.
Chicago Style (17th ed.) CitationStewart, Iain A. Deciding Whether a Planar Graph Has a Cubic Subgraph Is NP-complete. Newcastle upon Tyne, 1991.
MLA (9th ed.) CitationStewart, Iain A. Deciding Whether a Planar Graph Has a Cubic Subgraph Is NP-complete. 1991.
Warning: These citations may not always be 100% accurate.