Code-&-Results-quality.md

@@ -22,6 +22,13 @@ Actions taken within W-SLDA Toolkit to support the level 1 quality checks:
 
 ## Level 2: Internal tests
 
+While Level 1 actions are sufficient to detect most of errors that lead to results that are incorrect at the qualitative level, they are not sufficient to assure the correctness of the code computation at the quantitative level. The next level of teestign is<br> 
+&nbsp;&nbsp;&nbsp;_checking correctness of the computation for cases where solutions are know_.<br>
+Developers of W-SLDA Toolkit constantly seek for cases which can be used as test cases. 
+
+Actions taken within W-SLDA Toolkit to support the level 2 quality checks:
+* [Testsuite](https://gitlab.fizyka.pw.edu.pl/wtools/wslda/-/wikis/Testsuite): an automated system of executing test cases, that check correctenss of computation at the quantitative level. The automatic tests are executed routinely after each new commit to the main engine of the code. 
+
 ## Level 3: Open-source & Transparency