Puzzle 5

This is a Vigenère cipher. Key known to be less than 10 letters. Don't be put off by the length of the text. If working manually, use as large a fragment as you can deal with. More text means more redundancy which you can use.

ZLSYO KNGCE ZVGGH ZTKVE FKOIY QOPGX GRMKO QKEUI
KIZSS EZVAW HKUET SFXGR ODOKO STAVZ ILUJT VXWGP
ZXAEX EBKKI YSTZS TGVHZ GPOXM RTHKJ TZIEI CHYKH
AXWVY MTGID HITXC EZLKT FFZII XWEMT UASIY FEZWI
ZYKST KNIVV SJKRZ GCEBI TXWFT ANIBG XMYSB VXWUJ
KRXHU RCKHI TITZZ SXGSR YIZSP VTILM HEUQG XHVXJ
UVKYG XXIOJ URHCH YKEIX WMOXO IGFLE VVCKK GZMBX
VSCIF FXSLE BFXKG RWQGX OSBGX SBMRV JJUVW EZLKJ
WIYXV EFRMV GTVRH SBIHY KHKXO ZTMTK DFCIX WVRRP
XIELK WZEBV AXXEZ JZEZI CIYYI LOEUV MEBZF EZMCE
ZSARR VXXGO SKNIL YBTZM URGGK VLSFD KHARR VXXNI
DIKWK RHTUR BIBKO STFMR VVUXS TZMTK DFCIX HSJOK
TEHVJ FEXVV VEXXW VYXUE QFTJR MQKOJ VVCKK GZMCE
IETRC KHIGV FRTKK HOTIS XHWEM PEXVV JIZEW EORMT
CNKVY LOCRV KUIVY XUVGY GPREQ TKTZW ISPII XHFZL
KTFFB MYMCE YSLXV ZYEXX WTRIZ LSFLJ KVCWZ LKWSI
BMIIG FLENY ARTMZ EFZGR UVURT MFEHZ URYYQ YGWZL
SZTXK VBRZM UROCI SSQWK ZIKST KNIXI RTXSY WHFGW
YYAVZ LKLID GROXO IOETJ IEIXO SBJVI XJCIS IJFMG
XSZIQ KORMT CNKVY YBUKV ZLSGX IYIBK ISTZS EZMUR
OEERK YHIGP VSKVX SXEBP UVMEB ZFEZM CEORB MHVJF
EXVVV SCIFT URIIF EKHUV CWLIX MBXOX YIZWL SXXVV
YIVYF GUWKW GYGPR FSIKU AMFVJ XUEQK CMZLO JKRYI
CWXIY TCEYM HMZZZ CZSKR XHYXV VVEXX MKUXN IQFTJ
RMQKU RCLWT NTKVG FTWVV CKKGZ IRSEX NIDIK WKRHT
URBIB KOSTH SGKRJ EBUYL GPZSK VKUIZ XIJXC WAVTM
GYYYL JWTOI TXOJY YXEBT KWZLO KOXOW WEGTU WWKOS
TXCLT HKVHR QIZLS RVTXS DIOEZ ITLTG ZMCEY ETHHF
JMYGV RXKKX VVSMS TOIZM GPZPT SJIFF MEZMC ELVUQ
HYKTX IQVJM TKDIU ZOWWF TWYLO CRFKQ OUKFE WDVIM
GPOXX IKQSE ZWHIH NKITT CNKVY SBVUJ CLWTN MYVSJ
ZVOGH VJIBI BKKQV SFRXM RCWEO XYJFV KHUQH FTIMS
HZGXK AWKNX NICKN IXTCN KVUVW KYERP WVYFE VSRYS
TSTDO POXOI EIBIB KYQUV SGGVZ MQLRE XPMNN IXIHY
KANSZ VUVGW ISYXG RHZGP VEFKU JZLSK KVXMH FXCUJ
HYKWG MRGUA KVWJU GIYDZ KHCLS EKZKV WEZLK TFVYI
TXQFT ZKRHZ URSIB KOSTM GDGHK STRVV UXSTZ MTKDF
CIXWI TNQKR HZURG TDCOI YXCJA FYXWK AXKSF XGROD
OKOST WWEZL KWSEY IUJHY KTXIG VTXGV HZIPK

Please don't spoil the puzzle by posting a solution. Post help, or requests for help, by all means - but be circumspect.

A solution will appear in one week - so I won't be providing help :)