Grundlegung Online Comparison Tool
With this online webpage tool you can visually compare any line in any edition to the "matching" line(s) in any other edition of the Grundlegung included in the site. So, on the same webpage, in close proximity and alignment. you can quickly inspect four "matching" lines from four different editions of the Grundlegung. There are also options for varying the volume of output and for controlling the appearance of the results.