Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).

Backtrace:

(tail call): ?
Module:Citation/CS1/Configuration:2172: in function "init"
package.lua:103: ?
(tail call): ?
mw.lua:496: in function "executeModule"
mw.lua:768: in function "loadData"
Module:Citation_mode:9: in function "chunk"
mw.lua:496: ?
(tail call): ?
[C]: in function "xpcall"
MWServer.lua:99: in function "handleCall"
MWServer.lua:313: in function "dispatch"
MWServer.lua:70: ?
(tail call): ?
mw.lua:196: in function "old_pairs"
...ribunto/includes/Engines/LuaCommon/lualib/mwInit.lua:17: in function "pairs"
Module:Template_wrapper:85: in function "frame_args_get"
Module:Template_wrapper:158: in function "_main"
Module:Template_wrapper:231: in function "chunk"
mw.lua:527: ?
(tail call): ?
[C]: in function "xpcall"
MWServer.lua:99: in function "handleCall"
MWServer.lua:313: in function "dispatch"
MWServer.lua:52: in function "execute"
mw_main.lua:7: in main chunk
[C]: ?

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