deletions | additions       diff --git a/stuff to add.tex b/stuff to add.tex  index f7db21d..5c6da35 100644  --- a/stuff to add.tex  +++ b/stuff to add.tex 
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* standard references to Martin and the Germans who do this too on grids  * mention 2 electron case with singlet and triplet  * many different interactions and / or particle types