diff --git a/paper/paper.bib b/paper/paper.bib
index eb9080c..7c201f5 100644
--- a/paper/paper.bib
+++ b/paper/paper.bib
@@ -16,3 +16,21 @@ @article{julia
 	year    = {2017},
 	doi     = {10.1137/141000671},
 }
+@misc{MacroTools,
+  author       = {Mike Innes},
+  title        = {MacroTools.jl},
+  url = {https://github.com/FluxML/MacroTools.jl},
+  year = {2015},
+}
+@misc{SymEngine,
+  author       = {Development Team},
+  title        = {SymEngine.jl},
+  url = {https://github.com/symengine/SymEngine.jl},
+  year = {2015},
+}
+@misc{QSS,
+  author       = {Pietro, F. and Migoni, G. and Kofman, E.},
+  title        = {Improving linearly implicit quantized state system methods},
+  journal = {Simulation: Transactions of the Society for Modeling and Simulation International},
+  year = {2019},
+}