-er eee eef eel eep eer ees ef- efe eff efl efp efr efs ele elf ell elp elr els ep- epe epf epl epp epr eps ere erf erl erp err ers es- ese esf esl esp esr ess fee fef fel fep fer fes ffe fff ffl ffp ffr ffs fle flf fll flp flr fls fpe fpl fpp fpr fps fre frf frl frp frr frs fse fsf fsl fsp fsr fss l-p lee lef lel lep ler les lfe lff lfl lfp lfr lfs lle llf lll llp llr lls lpe lpf lpl lpp lpr lps lrf lrp lrr lrs lse lsf lsl lsp lsr lss p-p pee pef pel pep per pes pfe pff pfl pfp pfr pfs ple plf pll plp plr pls ppe ppf ppl ppp ppr pps pre prf prl prp prr prs ps- pse psf psl psp psr pss re- ree ref rel rep rer res rfe rff rfl rfp rfr rfs rle rlf rll rlp rlr rls rpe rpf rpl rpp rpr rps rrf rrl rrp rrr rrs rse rsf rsl rsp rsr rss se- see sef sel sep ser ses sfe sff sfl sfp sfr sfs sle slf sll slp slr sls spe spf spl spp spr sps sr- sre srf srl srp srr srs ss- sse ssf ssl ssp ssr sss