AT&T 6300 Programmer's Manual page 215

Example
COMMON
Statement
10 REM PG1
20 DIM A1(15,20)
30 COMMON A1( ),B1,C1
100 CHAIN "A:PG2"
110 END
10 REM PG2
50 PRINT A1(1,1)
90 END
A COMMON statement can also specify array
names. Such specifications are followed by a
pair of parentheses.
Each use of common array must be explicitly
described by a DIM statement in the
CHAINing program (but not in the CHAINed
one, otherwise a "Duplicated Definition" error
occurs).
The DIM statement must be written before the
associated COMMON statement.
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