diff --git a/book/contents/structures.md b/book/contents/structures.md
index 0381028..9659e4c 100644
--- a/book/contents/structures.md
+++ b/book/contents/structures.md
@@ -29,7 +29,7 @@ The following topics on **structures** are considered prerequisite knowledge for
|:------|:--------|:------------------|:---------------------------|
| Concrete Structures
[CTB2220](https://studiegids.tudelft.nl/a101_displayCourse.do?course_id=61996) | Material characteristics of concrete and reinforcement steel Student can:
- Identify Concrete and steel design properties according to the Eurocode |- [Properties for concrete ](https://eurocodeapplied.com/design/en1992/concrete-design-properties)[^29]
- [Properties for structural steel ](https://eurocodeapplied.com/design/en1993/steel-design-properties)[^30] |
| | Stress-strain relations in cross-sections Student can:
- Identify the stress-strain relationship in reinforced concrete cross-section |[Stress-strain relationship ](https://www.si-eng.org/post/a-step-by-step-anatomy-of-concrete-stress-strain-curve-1)[^31] |
-| | Design and verification of sections and members loaded under normal force, bending moment, shear force, torsion and/or combinations of these in SLS and ULS Student can:
- Make simple hand calculation to design different structural elements and verify them | - [Under normal force, bending moment and shear force ](https://structville.com/2020/10/design-of-reinforced-concrete-beams.html)[^32]
- [Under torsion ](https://structville.com/2021/01/worked-example-design-of-rc-beams-for-torsion-en-1992-12004.html)[^33]
- [Reinforcement calculation for different elements ](https://theconstructor.org/building/minimum-maximum-reinforcement-reinforced-concrete-elements/234426/)[^34] |For more information you can go through the following readers:
- [Slabs](../Lec_pdfs/Ch_14_EC_SlabsReader_nv_01.pdf)[^45]
- [Worked examples](../Lec_pdfs/CIE3150_CTB3335_2017_worked_examples_37.pdf)[^45]
+| | Design and verification of sections and members loaded under normal force, bending moment, shear force, torsion and/or combinations of these in SLS and ULS Student can:
- Make simple hand calculation to design different structural elements and verify them | - [Under normal force, bending moment and shear force ](https://structville.com/2020/10/design-of-reinforced-concrete-beams.html)[^32]
- [Under torsion ](https://structville.com/2021/01/worked-example-design-of-rc-beams-for-torsion-en-1992-12004.html)[^33]
- [Reinforcement calculation for different elements ](https://theconstructor.org/building/minimum-maximum-reinforcement-reinforced-concrete-elements/234426/)[^34]
- [Reader I: Slabs](../Lec_pdfs/Ch_14_EC_SlabsReader_nv_01.pdf)[^45]
- [Reader II: Worked examples](../Lec_pdfs/CIE3150_CTB3335_2017_worked_examples_37.pdf)[^45] |- Two alternatice sources for torsion is provided at "Under torsion" and "Reader II: Worked examples" (see examples 19, 20 and 21.)
- In depth information can be read in the provided readers.
| | Detailing of concrete and reinforcement Student can:
- Make simple hand calculation to determine the minimum required reinforcement for different structural elements and verify them |[Beam reinforcement detailing ](https://www.structuralguide.com/beam-reinforcement-detailing/)[^35] |
| | Crack-width control Student can:
- Make simple hand calculation to determine the crack width for different structural elements and control their size | [Crack-width control](../Lec_pdfs/Ch_15_EC_Crack_width_control_CRB_07_V2018.pdf)[^36] |- See if you can do example 1 and example 2 at the end of the document
- Go through the reader if needed for the theory
| | Deformation of concrete structures Student can:
- Identify how structures can deform and the effects deformation can cause | [Defects in Concrete Structures ](https://theconstructor.org/concrete/concrete-defects-types-causes-prevention/8581/#:~:text=Different%20types%20of%20defects%20in,to%20various%20reasons%20or%20causes.)[^37] ||