Álvaro Romero Jiménez David Orellana-Martín Design Patterns for Efficient Solutions to NP-Complete Problems in Membrane Computing. 237-255 2018 Enjoying Natural Computing https://doi.org/10.1007/978-3-030-00265-7_19 conf/birthday/2018pj db/conf/birthday/PerezJimenez2018.html#JimenezO18