Humanities and social science teaching assistants yesterday delivered the Yale University administration an ultimatum: grant them union representation or they will walk off the job.

Members of the Yale Graduate Employee and Student Organization (GESO) voted Monday night that if Yale does not recognize them by March 31, they will not work the week of April 3.

"It was overwhelming. Ninety percent of the people there voted to set a deadline. It was a very clear message," said Eve S. Weinbaum, GESO spokesperson.

"We had sleet and ice here [Monday] night," she said. "Over 500 people came out, even in that weather. That's over half of the graduate students."

The job action is scheduled to last a week, GESO leaders say they're not planning an further action.

GESO leaders sent a letter to Yale President Richard Levin informing him of the vote and once again demanding an election. But Yale officials yesterday reiterated their refusal to recognize the graduate students as a bargaining unit.

"The answer is 'Have a nice day," said Gary G. Fryer, Yale's director of public affairs. "They know very well we do not recognize them as a bargaining unit, and we have no intention of recognizing them."

"They are students principally, not employees, and they are treated as such," he said. "We will not bargain with them or treat them as employees."

But Weinbaum maintained there is a chance Yale will recognize GESO as a union.

"We're just beginning to talk to undergraduates and faculty about what's happening here," she said. "I think they'll start to feel more pressure. A lot could happen in the next five weeks."

She said GESO members would continue to meet with administrative officials and try to work out a deal.

"We're going to do everything we can to avoid [the job action]," Weinbaum said. "We felt that this would be the most civilized and reasonable way to deal with things. If they refuse ahead with it."

Fryer refused to speculate on what would happento those teaching assistants (TAs) who choose towalk out this spring.

"There's a certain degree of theater associatedwith this. We have no intention in participatingin that," Fryer said.

"Our view would be that we would prefer that noaction be taken," he continued. "But theuniversity would go on, and instruction would goon."

Levin told the Yale Daily News Monday that thewalk out would not have a detrimental effect onthe education that undergraduates receive at theuniversity

"TAs are not the primary instructors involvedin teaching undergraduates," Levin said in aninterview with Yale's daily student newspaper.

If GESO does refuse to work in April, "we willcarry out our responsibility to offer classes toundergraduate students," Levin said