The electronic conferences conducted on computer networks provide another fertile source of cool code.

These works were a fertile source of material for William Shakespeare and other authors.

The camps they'd set up to oppress the people had become fertile sources of intelligence against them.

In theory, Mills has created a fertile source of satire.

Loose mouths can be a fertile source of trouble and we want no trouble.

This was a fertile source of incomprehension between him and Ellen.

The most fertile sources for recruiting new members are lists rented from credit card companies.

It is believed that there may be a more fertile source elsewhere in the area, a possibility being investigated by a private company.

The urban environment is also becoming a fertile source for younger artists.

As maintained by Watson, transplantation is the most fertile source of legal development.