Celandine removal

We moved to a new house last May which has a small garden much of it consisting of a large flower bed roughly 15mtrs x 5mtrs which now is completely covered with Celandine.
As I have severe back problem it is impossible for me to try and dig these out, therefore can someone recommend a suitable weed killer that would do the job.

Many thanks.

 

Celandine removal from the rhs website.

 

i have lesser celandine, Ranunculus ficaria, pile wort; growing in quite a few places among other plants so weedkiller is out. Removing by hand is a pain as it spreads easily from any of the small tubers left or dropped; these small tubers also survive most domestic compost heaps, so it's either the council garden waste of immerse in water until reduced to sludge.
The good side of them, I actually rather like them, except in the raised bed where I grow a lot of small bulbs; is that they are quite a cheerful yellow flower with glossy green foliage in early spring and a few weeks after flowering they disappear until the following year.

 

Well I did think they kind of disappeared over the summer but wasn't sure.
I have a few that appear on my allotment and find them a nice feature in early spring.

But I can see as how maybe a complete bed of them could be a bit much.