Fix broken ref links

tutorials/physics/rigid_body.rst

@@ -12,11 +12,11 @@ In order to define the shape of the body, it must have one or more :ref:Shape <c
 How to control rigid body
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-A rigid body's behavior can be altered by setting its properties such as friction, mass, bounce, etc. These properties can be set in the Inspector or via code. See :ref:RigidBody <class_RigidBody> for the full list of properties and their effects.
+A rigid body's behavior can be altered by setting its properties such as friction, mass, bounce, etc. These properties can be set in the Inspector or via code. See :ref:`RigidBody <class_RigidBody>` for the full list of properties and their effects.
 
 There are several ways to control a rigid body's movement, depending on your desired application.
 
-If you only need to place a rigid body once, for example to set its initial location, you can use the methods provided by the :ref:Spatial <class_Spatial> node, such as ``set_global_transform()`` or ``look_at()``. However, these functions can not be called every frame or the physics engine will not be able to correctly simulate the body's state.
+If you only need to place a rigid body once, for example to set its initial location, you can use the methods provided by the :ref:`Spatial <class_Spatial>` node, such as ``set_global_transform()`` or ``look_at()``. However, these functions can not be called every frame or the physics engine will not be able to correctly simulate the body's state.
 As an example, consider a rigid body that you want to rotate so that it points towards another object. A common mistake when implementing this kind of behavior is to use ``look_at()`` every frame, which breaks the physics simulation. Below, we'll demonstrate how to implement this correctly.
 
 The fact that you can't use ``set_global_transform()`` or ``look_at()`` methods doesn't mean that you can't have full control of a rigid body. Instead, you can control it by using the ``_integrate_forces()`` callback. In this function, you can add *forces*, apply *impulses*, or set the *velocity* in order to achieve any movement you desire.