by (或 on) request

in response to an expressed wish

应（某人）请求

by request

In response to an expressed desire

应…的要求

We are offering these scarves for sale again by request.

应大众要求我们再次出售这些头巾

in request

In great demand

受欢迎

a pianist in great request.

极受欢迎的钢琴家

on request 或 upon request

When asked for

一经要求

References are available on request.

有参考资料备索