modelica · tobolar · Mar 10, 2026 · Mar 20, 2026 · Apr 10, 2026 · Apr 10, 2026
diff --git a/Modelica/Mechanics/MultiBody/Frames/Quaternions/from_T.mo b/Modelica/Mechanics/MultiBody/Frames/Quaternions/from_T.mo
@@ -14,7 +14,7 @@ protected
 algorithm
   /*
    This is an optimized version of the quaternion conversion based on
-   this paper: https://d3cw3dd2w32x2b.cloudfront.net/wp-content/uploads/2015/01/matrix-to-quat.pdf
+   this paper: modelica://Modelica/Resources/Documentation/Mechanics/matrix-to-quat.pdf
 */
   if T[3, 3] < 0 then
     if T[1, 1] > T[2, 2] then
@@ -74,7 +74,7 @@ package.
 <ul>
   <li>January 2021 by Jakub Tobolar<br>
        reimplemented for more efficient and numerically stable algorithm according to
-       <a href=\"https://d3cw3dd2w32x2b.cloudfront.net/wp-content/uploads/2015/01/matrix-to-quat.pdf\">https://d3cw3dd2w32x2b.cloudfront.net/wp-content/uploads/2015/01/matrix-to-quat.pdf</a>.
+       <a href=\"modelica://Modelica/Resources/Documentation/Mechanics/matrix-to-quat.pdf\">matrix-to-quat.pdf</a>.
        It compares only one particular diagonal element with another to
        select one of the four code parts. Then, the selected code delivers
        four components which are close to the desired quaternion,

diff --git a/Modelica/Resources/Documentation/Mechanics/matrix-to-quat.pdf b/Modelica/Resources/Documentation/Mechanics/matrix-to-quat.pdf