Most likely the users are not willing to change their source of supply.

很可能用户不愿改变他们的供货来源。

youdao

Another potential source of supply is sitting in the vaults of central Banks.

另一个潜在的供给来源是央行的金库。

youdao

The third main source of supply is scrap: jewellery sold to dealers for the value of the metal.

第三大供给来源自黄金回收：首饰商按金属价值卖给金贩子。

youdao

it creates a new source of supply; it creates new management.

VOA: standard.2010.01.31

In short, what was once a source of supply is now a source of demand.

FORBES: Year of the Golden Rabbit

Coke's primary source of supply for orange juice sold in the U.S. is Florida.

WSJ: Coke, Pepsi Attempt to Ease O.J. Fears

Relying on a single source of U.S demand and single source of supply would be the pinnacle of economic stupidity.

FORBES: Why China Will Stop U.S. Energy Independence