In[55]:=
  mixedderivterms = Drop[%%%%,-7]

Out[55]=

                       p                          p
  -(sigma       sigma      ) - sigma       sigma       - 
         ;pafgh      ;b cde         ;paegh      ;b cdf
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;paefh      ;b cdg        ;paefg      ;b cdh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;padgh      ;b cef        ;padfh      ;b ceg
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;padfg      ;b ceh        ;padeh      ;b cfg
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;padeg      ;b cfh        ;padef      ;b cgh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pacgh      ;b def        ;pacfh      ;b deg
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pacfg      ;b deh        ;paceh      ;b dfg
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;paceg      ;b dfh        ;pacef      ;b dgh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pacdh      ;b efg        ;pacdg      ;b efh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pacdf      ;b egh        ;pacde      ;b fgh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabgh      ;c def        ;pabfh      ;c deg
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabfg      ;c deh        ;pabeh      ;c dfg
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabeg      ;c dfh        ;pabef      ;c dgh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabdh      ;c efg        ;pabdg      ;c efh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabdf      ;c egh        ;pabde      ;c fgh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabch      ;d efg        ;pabcg      ;d efh
   
                       p                         p
    sigma       sigma       - sigma       sigma       - 
         ;pabcf      ;d egh        ;pabce      ;d fgh
   
                       p                        p
    sigma       sigma       - sigma      sigma        - 
         ;pabcd      ;e fgh        ;pfgh      ;a bcde
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pegh      ;a bcdf        ;pefh      ;a bcdg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pefg      ;a bcdh        ;pdgh      ;a bcef
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pdfh      ;a bceg        ;pdfg      ;a bceh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pdeh      ;a bcfg        ;pdeg      ;a bcfh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pdef      ;a bcgh        ;pcgh      ;a bdef
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pcfh      ;a bdeg        ;pcfg      ;a bdeh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pceh      ;a bdfg        ;pceg      ;a bdfh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pcef      ;a bdgh        ;pcdh      ;a befg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pcdg      ;a befh        ;pcdf      ;a begh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pcde      ;a bfgh        ;pbgh      ;a cdef
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbfh      ;a cdeg        ;pbfg      ;a cdeh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbeh      ;a cdfg        ;pbeg      ;a cdfh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbef      ;a cdgh        ;pbdh      ;a cefg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbdg      ;a cefh        ;pbdf      ;a cegh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbde      ;a cfgh        ;pbch      ;a defg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbcg      ;a defh        ;pbcf      ;a degh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pbce      ;a dfgh        ;pbcd      ;a efgh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pagh      ;b cdef        ;pafh      ;b cdeg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pafg      ;b cdeh        ;paeh      ;b cdfg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;paeg      ;b cdfh        ;paef      ;b cdgh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;padh      ;b cefg        ;padg      ;b cefh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;padf      ;b cegh        ;pade      ;b cfgh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pach      ;b defg        ;pacg      ;b defh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pacf      ;b degh        ;pace      ;b dfgh
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pacd      ;b efgh        ;pabh      ;c defg
   
                      p                         p
    sigma      sigma        - sigma      sigma        - 
         ;pabg      ;c defh        ;pabf      ;c degh
   
                      p                         p                         p
    sigma      sigma        - sigma      sigma        - sigma      sigma
         ;pabe      ;c dfgh        ;pabd      ;c efgh        ;pabc      ;d efgh

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