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 </p>
 
 
-**Geoloop** is a Python package for simulating borehole heat exchanger (BHE) systems,
-with a focus on optimal implementation of subsurface thermal properties and their impact on system performance.
+**Geoloop** is a Python package for simulating vertical borehole heat exchanger (BHE) systems,
+with a focus on the impact of depth-dependent thermal properties and geothermal gradient and their impact on system performance.
 
 **Geoloop** incorporates (uncertainty in) depth-variations in subsurface thermal conductivity, subsurface temperature, 
 BHE design and diverse operational boundary conditions such as seasonal load variations or 
-minimum fluid temperatures, in a tool for deterministic or stochastic performance analyses with the opportunity
-for optimization of the system design and operation. This makes Geoloop ideal for scenario analyses and sensitivity 
+minimum fluid temperatures. It allows for deterministic or stochastic performance analyses with the opportunity
+for optimization of the system design and operation. This makes Geoloop well suited for scenario analyses and sensitivity 
 studies in both research and practical applications.
 
-**Geoloop** uses thermal response factors (*g*-functions) calculated using the analytical Finite Line Source model from 
-the *pygfunction* package. This setup is extended into a stacked approach for depth-dependent thermal response calculations. 
-A detailed description and benchmark of this depth-dependent semi-analytical method is provided in Korevaar & Van Wees (in prep.).
-**Geoloop's** generic framework allows for easy switching between simulation methods, including the innovative depth-dependent
-semi-analytical approach, the depth-uniform implementation of g-functions as implemented in *pygfunction* and a numerical 
+**Geoloop**  provides a novel depth-dependent approach for thermal response calculations. 
+A detailed description and benchmark of this depth-dependent semi-analytical method is provided in Korevaar et al. (2026).
+**Geoloop** uses the *pygfunction* package, developed by Cimmino & Cook (2022), including its implementation
+of *g*-functions, time aggregation schemes for varying loads, borehole and fluid thermal properties, and various visualization capabilities
+
+**Geoloop's** generic framework allows for easy switching between simulation methods, including the 
+depth-dependent model, the depth-uniform implementation of g-functions as implemented in *pygfunction* and a numerical 
 finite volume approach.
 
 ---
@@ -44,6 +46,16 @@ For the theoretical background, see the [Theory](theory/theory.md) page.
 *Geoloop* was developed as part of an innovation project with industry partners (grant no. **MOOI322009**),
 funded by the **Dutch Ministry of Climate and Green Growth**.
 
+---
+
+## References
+
+- Cimmino, M. and Cook, J.: pygfunction 2.2: New features and improvements in accuracy and computational efficiency, 
+        in: Proceedings of the IGSHPA Research Track 2022, International Ground Source Heat Pump Association, 
+        https://doi.org/10.22488/okstate.22.000015, 2022. 
+- Korevaar, Z., Brett, H., Van Wees, J.D.: Geoloop (v1.0) – a stochastic, depth-dependent borehole heat exchanger model, Geoscientific Model Development (in prep), 2026
+
+---
 
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   <img src="logo_images/TNO_logo.png" style="height:60px;margin-right:20px;">
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