A different version of Caroline Club maintained by Floyd McWilliams
may be of interest, but as of 2020 is not available at the linked location. Probably over 95% of the system is similar
between these versions. No other Caroline Club pairs are known to have
archived system notes on the web.
A WBF convention card for Ekeblad-Rubin may be of interest except it is no longer available at the linked location. Caroline Club is based on methods of Ekeblad-Sukoneck, the later Ekeblad-Rubin methods are similar in many respects. A detailed examination of system differences is beyond the scope of this webpage, however.