The most famous Bulgarian rune symbol- IYI is carved on the back of the rosette. This is the symbol of the Sun and expresses the religious ideas of protobulgarians. Some researchers believe this is the sign of Bulgarian dynasty Dullo, who found the Bulgarian state.
                I Y I  is rendered as JUJI
Hence    I   Y   I 
                J  U  JI
Upsilon with two posts - ІYI. In protos-Bulgarian the sign ІYI had wide [rassprostranenie]. It is encountered in all territories, where the protos-Bulgarian were: Danube Bulgaria, Rumania, [Shudikovo] in the black mountain. [L].[Doncheva]-[Petkova] indicated [Muntenaya] region, [Banat], southern [Moldova], southern transylvania, as the zones of [rassprostraneniya] of sign ІYI, [resp]. in transdanube Bulgaria (north [r].[Dunay]), in 9-10 v. (LD- P -[ZAPSb], [str].23) it is encountered also in the Caucasus - The [khumarinskoe] fortification. Similar signs ұ were [naydenny], also, on the bricks from the [Er]- barrow, the capital of [kidaritov]-[eftalitov] in the oasis [Karshi], to Bukhara. In the ruins of Bulgarians city, the archaeologist [Rafin] Of [shariffulin] ([Sharifullin]) Volga -[bulgarskogo] found among the lead and gold objects of dated to 12-13 substances, original gold rings with the image of sign ІYI. [V].[Beshevliev] connected this sign with the cult of supreme deity. IYI sketched on the different of graffiti, hollowed on [kirpichyakh], stones, plates, water pipes, ceramic vessels, rings, amulets, helmets. Sign they incorrectly connected with [tagmoy] of kind muzzle, this of number or the sign of master- builder, [kamenodeltsa] and so forth wide [rassprostranenie] on the building materials and the plates and on the everyday objects and the vessels, entirely clearly shows its sacral sense - preventing, [zaklinatelnyy], religious formula. For protection of house and its inhabitants from the poor forces (evil forces), anger of god (gods) and his punishments. In the first runic inscriptions after christianization, sign Y they wrote as the analog of cross. (WB- P, [str].70-71) in some regions of Bulgaria ([obl].[g].[Smolena], the mountains Of [rodopi]) sign IYI preserved [sya] to 20 v., it was placed on the ritual grain crops, [prigotvlennykh] to the different religious holidays. IYI existed (before the reform of Bulgarian spelling after [komunisticheskogo] revolution in 09.09.1944 g.) and as one of the specific Bulgarian letters - [malenkaya] [nosovka] (capital letter?) -, which in the old-Bulgarian was pronounced as „it”. In „to rosette of [Pliski]” we see one earlier version -, with those zh by sonic pronunciation - „it” or „of [n]”. ([IT]-[IPNPB]) in the later editorial staff is discovered this sign into „To [tallaskoy] plate” - and into [alano]-[protobolgarskikh] (Don- Kuban) runes from The [khumarinskogo] fortification and [Sarkela] -, with sonic [ravnostoynostyu] (the same pronunciation) “[ut], from, quarter deck”. ([GT]-[PPYANKVE], table, [KHKHKH]І[KH]) connection it- from occurs from the nose pronunciation and the passage it-[ont]- from. Is possible semantic connection with the [alano]- the Sarmatian od - shower, spirit, in the ossetic [ironskom] ud, [digorskom] of u[e]d - spirit, [bozhestvenaya] force ([V].[Abaev]). ([ORS]), ([DRS]) the root of *en/*on also very ancient, [paleolitnyy] (boreal) on the origin designates god and sky, in the [shumerskom] ene, [enki], [enlil] - sky, god, Basque jainko - god and Latin anima - soul, spirit. In the African tribes of [masai] and [samburo], that dwell in Kenya, supreme deity bore the name Of [enkay]. http://www.protobulgarians.com/Russian%20translations/Zhivko%20Voynikov%20-%20Alano-drevnebolgarskoe%20pismo/ALANO-DR-BOLG-PISMO/AL-PRB-P-13.htm