But as a substitute, he said, he will ask businesses in his city to voluntarily contribute support for a district like New York's.

All regular and guest authors contribute strictly voluntarily.

Physicians in the field agreed to voluntarily contribute their patient data to this outcomes registry.

Instead, it said rich countries should voluntarily contribute to an education fund.

Many users voluntarily contribute to community building and maintenance (e.g., as conference hosts).

Social security applies to self-employed workers, who voluntarily contribute between 12% and 18% of income depending on the protection sought.

Some US states offer income tax checkoffs to contribute voluntarily to various state programs.

In the UK there are over 6,250 volunteers, who contribute over 500,000 hours a year voluntarily.

Anonymous is rallying participants to voluntarily contribute to the denial of service attack on Sony.

If a majority would not voluntarily contribute, then most individuals disagree with the premise of Social Security.