| Article ID: | iaor20133945 |
| Volume: | 206 |
| Issue: | 1 |
| Start Page Number: | 577 |
| End Page Number: | 583 |
| Publication Date: | Jul 2013 |
| Journal: | Annals of Operations Research |
| Authors: | Janiak Adam, Kovalyov Mikhail, Lichtenstein Maciej |
| Keywords: | learning |
Proofs of strong NP‐hardness of single machine and two‐machine flowshop scheduling problems with learning or aging effect given in Rudek (2011; 2012a; 2012b; 2012c; 2013) contain a common mistake that make them incomplete. We reveal the mistake and provide necessary corrections for the problems in Rudek. NP‐hardness of problems in Rudek remains unknown because of another mistake which we are unable to correct.