Citation information:

Luebeck, Roger. Relativity Trail. Minneapolis: Little Bear Writ Publishing, (2008)

Luebeck, Roger (2008, Sept 1). Relativity Trail. https://relativitytrail.com/relativitytrail.pdf

Annotation:

In this book, the symmetrically measured effects of the
special theory of relativity are explained with diagrams 
and arithmetic arising from an absolute frame of reference, 
which is intrinsic to the evolving structure of the universe.  
This rest state of the totality of the universe is not 
experimentally detectable.  Absolute versions of Einstein's 
"postulates of measure" are incorporated.  Although time 
keeping and distance acquire meaning in absolute terms, 
Relativity Trail is completely consistent with Einstein's 
treatment.  No clock paradox arises, as the time differential 
between reunited clocks is seen to be caused by an actual 
difference in clock rates in accordance with their different 
states of motion in relation to the speed of light.