Rigorous peer-review is the corner-stone of high-quality academic publishing. The editorial team greatly appreciates the reviewers who have dedicated their considerable time and expertise to the journal’s rigorous editorial process over the past 12 months, regardless of whether the papers are finally published or not. In 2019, a total of 50 papers were published in the journal, with a median time to first decision of 13.5 days and a median time from submission to publication of 36.5 days. The editors would like to express their sincere gratitude to the following reviewers for their generous contribution in 2019:
| Abarca-Alvarez, Francisco Javier | Modoni, Gianfranco |
| Abdel-Nasser, Mohamed | Morimoto, Yasuhiko |
| Abiri, Reza | Moscato, Vincenzo |
| Aghajani, Haleh | Murtagh, Fionn |
| Alcayde, Alfredo | Narayanan, Barath |
| Almgren, Khaled | Nasridinov, Aziz |
| Anysz, Hubert | Netek, Rostislav |
| Arroyo-Figueroa, Gustavo | Otoum, Safa |
| Babič, František | Ovalle, María Antonia |
| Babulak, Eduard | Paap, Kenneth R. |
| Baker, Thar | Paiva, Sara |
| Bárcena, Elena | Palani, Hari |
| Bernardino, Jorge | Palos-Sánchez, Pedro |
| Bobulski, Janusz | Pang, Jun |
| Brescia, Massimo | Patel, Sarosh |
| Chen, Chi-Yuan | Patil, Madhav |
| Cho, Young Im | Paulauskas, Nerijus |
| Ciaburro, Giuseppe | Pavlidis, Michalis |
| Cotfas, Liviu-Adrian | Perikos, Isidoros |
| Cutchin, Steve | Pirjan, Alexandru |
| Damasevicius, Robertas | Pławiak, Paweł |
| De Mingo López, Luis Fernando | Połap, Dawid |
| Diaconita, Vlad | Przegalinska, Aleksandra |
| Dreżewski, Rafał | Ravankar, Abhijeet |
| Elshaw, Mark | Regulski, Krzysztof |
| Fernandez Hilario, Alberto | Relich, Marcin |
| Garg, Harish | Santos, Juan M. |
| Gašparović, Mateo | Sarnè, Giuseppe Maria Luigi |
| Geng, Ruili | Saura, José Ramón |
| Gil, David | Segall, Richard |
| González Pérez, Isaías | Sengupta, Saptarshi |
| González-Briones, Alfonso | Sepasgozar, Samad |
| Grecu, Valentin | Seritan, George |
| Grout, Vic | Sicilia-Montalvo, Juan Antonio |
| Gulić, Marko | Sperlì, Giancarlo |
| Guliciuc, Viorel | Stella, Massimo |
| Huo, Yiming | Suciu, George |
| Hussain, Muhammad Majid | Sun, Peng |
| Igual, Jorge | Sun, Ziheng |
| Ijaz, Muhammad Fazal | Surian, Didi |
| Iliyasu, Abdullah M. | Syafrudin, Muhammad |
| Jeong, Dong Hyun | Szénási, Sándor |
| Johannssen, Arne | Templ, Matthias |
| Judge, Mark | Torti, Emanuele |
| Kania, Krzysztof | Tsiakas, Konstantinos |
| Kapuscinski, Tomasz | Tsiropoulou, Eirini Eleni |
| Karakatič, Sašo | Turanoglu Bekar, Ebru |
| Kastrin, Andrej | Tyshchenko, Oleksii |
| Kaufmann, Michael | Varlamis, Iraklis |
| Konys, Agnieszka | Vassilakis, Costas |
| Korzun, Dmitry | Wallace, Manolis |
| Kotter, Richard | Wang, Cheng |
| Li, Jichao | Wöhrer, Alexander |
| Liu, Ye | Yu, Liangjiang |
| Livieris, Ioannis E. | Zamani, Mazdak |
| Maestre Vidal, Jorge | Zbořil, František |
| Maniou, Theodora | Zhang, Lijun |
| Martínez López, Luis | Zhang, Yu |
| Mavragani, Amaryllis | Zhou, Xujuan |
| Mehrotra, Prakhar |
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