code: public Quaternionf rotateAxis(float angle, float axisX, float axisY, float axisZ) {
          return rotateAxis(angle, axisX, axisY, axisZ, this);
      }
docs: Apply a rotation to <code>this</code> quaternion rotating the given radians about the specified axis.
  <p>
  If <code>Q</code> is <code>this</code> quaternion and <code>R</code> the quaternion representing the
  specified rotation, then the new quaternion will be <code>Q * R</code>. So when transforming a
  vector <code>v</code> with the new quaternion by using <code>Q * R * v</code>, the
  rotation added by this method will be applied first!
  
  @see #rotateAxis(float, float, float, float, Quaternionf)
  
  @param angle
  the angle in radians to rotate about the specified axis
  @param axisX
  the x coordinate of the rotation axis
  @param axisY
  the y coordinate of the rotation axis
  @param axisZ
  the z coordinate of the rotation axis
  @return this