The phrase "agreed variation" is correct and usable in written English.
It can be used in contexts where parties have come to a mutual understanding or consensus regarding a change or modification to an agreement or plan.
Example: "After much discussion, we reached an agreed variation to the original contract that accommodates both parties' needs."
Alternatives: "mutually accepted change" or "consensus modification".
The experts who contributed to a two-month series on the Op-Ed page called "Is the Cold War Over?" agreed, with variations in emphasis and definition, that Soviet-American relations are entering a new era.
Derek Muir of the National Water Research Institute in Burlington, Canada, agrees that variation in enantiomers can play a big role in determining ecotoxicity.
We agree that variation in smoking behaviour and composition of smoke in different waterpipe-smoking settings are very likely.
The observed levels of protein variation agreed well with those observed at the nucleotide level, finding high levels of silent variation.
The analytically calculated magnetic flux density variation agreed to within 5.6% with the experimental value for the center point of the magnet gap.
The attorney general's office said: "The BBC and the attorney general today agreed to a variation of the injunction obtained on Friday concerning a particular document relating to the 'cash for honours' police investigation.
Analyst Andy Chambers at Cantor Fitzgerald said: Ahead of tomorrow's 2013 results BAE has this morning announced that the UK and Saudi governments have agreed the price variation on the Salam contract for the supply of 72 aircraft to the kingdom.
As a matter of fact, with the temperature increasing from 120°C to 210°C, the evolution of the BET specific surface area, total pore volume, and average pore diameter of the various-morphology pod-like α-Fe2O3 nanoarchitectures agreed with the variation of the D104 calculated by the Debye-Scherrer equation, also in accordance with the SEM observation (Figure 2d,e,f,g,h).
Molecular clock analysis of chlorotype variation agreed with phylogenetic analyses in indicating the divergence of species long predating the LGM.
