"first indicated" is a correct and usable phrase in written English.
It can be used to describe when something was mentioned or indicated for the first time. For example, "He first indicated the plan at the meeting yesterday."
Having at first indicated that he was likely to take no further action, the indications on Monday night were that the rider will appeal against the ban.
Mr. Green first indicated last month that he would make a bid.
The Rothschild family in 2013 first indicated it wanted to sell the paintings, NRC added.
From the perspective of the robot processing mechanism, the key role of the per-load pressing force is first indicated.
She first indicated that she would run for Representative Rahm Emanuel's Congressional seat when he becomes Mr. Obama's chief of staff, but decided against it.
Inquiry staff first indicated they knew nothing about the Libyan operations, and were seeking information from the government "as soon as possible".
The meeting had been actively discussed since mid-October, when the rebels first indicated that they would accept Mr. Putin's offer for discussions.
Mueller first indicated to Trump's lawyers in December 2017 that he wanted to interview the president in a face-to-face session to complete his investigation.
What's disturbing from a scientific angle, however, are reports that independent studies that first indicated a problem in Flint were initially simply dismissed.
The first indicated a mediating effect whereby perceived academic competence mediated the relationship between attachment security to the mother and mastery goal orientation.
Since Mr. Bernanke first indicated in May that he might step back from the bond purchases, investors have sold mortgage bonds and pushed mortgage rates up.
