De or het ledenreferendum?

The correct Dutch article is:

het ledenreferendum

Rule Words ending in -um and -ium: usually het. See the rule

How to use ledenreferendum

the ledenreferendumhet ledenreferendum
this ledenreferendumdit ledenreferendum
that ledenreferendumdat ledenreferendum
our ledenreferendumons ledenreferendum
your ledenreferendumjouw ledenreferendum
every ledenreferendumelk ledenreferendum
which ledenreferendum?welk ledenreferendum?
a big ledenreferendum / the big ledenreferendumeen groot ledenreferendum, het grote ledenreferendum