@LabPlot The abstract appears to be talking about free software only. Their use of OSS only helps to spread #ignorance of the difference between open-source and free software. (#Microsoft and the #OSI are happy to keep such ignorance alive as part of Microsoft's EEE strategy for free software.)
Use of the wrong term, OSS, could lead to funding going to proprietary OSS rather than free software development. #vigilance is always needed.