This book constitutes the refereed proceedings of the 13th International SPIN workshop on Model Checking Software, SPIN 2006, held in Vienna, Austria in March/April 2006 as satellite event of ETAPS 2006. The 16 revised full papers presented together with three tool presentation papers were carefully reviewed and selected from 44 submissions. The papers are organized in topical sections.

This book constitutes the proceedings of the 36th International Conference on Application and Theory of Petri Nets and Concurrency, PETRI NETS 2015, held in Brussels, Belgium, in June 2015. The 12 regular papers and 2 tool papers presented in this volume were carefully reviewed and selected from 34 submissions. In addition the book contains 3 invited talks in full paper length. The papers cover various topics in the field of Petri nets and related models of concurrency.