-er eee eef eel eep eer ees ef- efe eff efi efl efp efr efs eie eif eii eil eip eir eis ele elf eli ell elp elr els ep- epe epf epi epl epp epr eps ere erf eri erl erp err ers es- ese esf esi esl esp esr ess fee fef fei fel fep fer fes ffe fff ffi ffl ffp ffr ffs fie fif fii fil fip fir fis fle flf fli fll flp flr fls fpe fpi fpl fpp fpr fps fre frf fri frl frp frr frs fse fsf fsi fsl fsp fsr fss i-f ie- iee ief iei iel iep ier ies ife iff ifi ifl ifp ifr ifs iie iif iii iil iip iir iis il- ile ilf ili ill ilp ilr ils ipe ipf ipi ipl ipp ipr ips ir- ire irf iri irl irp irr irs is- ise isf isi isl isp isr iss l-p lee lef lei lel lep ler les lfe lff lfi lfl lfp lfr lfs lie lif lii lil lip lir lis lle llf lli lll llp llr lls lpe lpf lpi lpl lpp lpr lps lrf lri lrp lrr lrs lse lsf lsi lsl lsp lsr lss p-p pee pef pei pel pep per pes pfe pff pfi pfl pfp pfr pfs pie pif pii pil pip pir pis ple plf pli pll plp plr pls ppe ppf ppi ppl ppp ppr pps pre prf pri prl prp prr prs ps- pse psf psi psl psp psr pss re- ree ref rei rel rep rer res rfe rff rfi rfl rfp rfr rfs rie rif rii ril rip rir ris rle rlf rli rll rlp rlr rls rpe rpf rpi rpl rpp rpr rps rrf rri rrl rrp rrr rrs rse rsf rsi rsl rsp rsr rss se- see sef sei sel sep ser ses sfe sff sfi sfl sfp sfr sfs sie sif sii sil sip sir sis sle slf sli sll slp slr sls spe spf spi spl spp spr sps sr- sre srf sri srl srp srr srs ss- sse ssf ssi ssl ssp ssr sss