Update ISO standard Link

Author: ishan372or

docs/source/blog/displacement-vectors.md

@@ -47,7 +47,7 @@ If you need a drop-in replacement for the old behaviour, you can use:
 
 __Related changes__
 
-We slightly modified the behaviour of vector conversion from Cartesian to polar coordinates. For simplicity and interpretability, {func}`cart2pol <movement.utils.vector.cart2pol>` now always sets the angle `phi` to 0 when the vector's norm `rho` is 0, rather than following the [C standard](https://www.iso.org/standard/29237.html) for [`arctan2`](https://en.wikipedia.org/wiki/Atan2). This change should not affect existing workflows, as a zero-length vector has an undefined direction—meaning it could point in any direction, and assigning `phi = 0` is a safe, neutral choice.
+We slightly modified the behaviour of vector conversion from Cartesian to polar coordinates. For simplicity and interpretability, {func}`cart2pol <movement.utils.vector.cart2pol>` now always sets the angle `phi` to 0 when the vector's norm `rho` is 0, rather than following the [C standard](https://www.iso.org/standard/82075.html) for [`arctan2`](https://en.wikipedia.org/wiki/Atan2). This change should not affect existing workflows, as a zero-length vector has an undefined direction—meaning it could point in any direction, and assigning `phi = 0` is a safe, neutral choice.
 
 ## Reflections