The exact chronology of the poems is not known.

The exact chronology of the Wajihid dynasty is difficult to determine.

I figured if the cops wanted an exact chronology, I should have one, too.

However, some of the action can be connected with dates, although it is unclear if Stevenson had an exact chronology in mind.

Sources are divided on the exact chronology and motives of the revolt.

It is difficult today to determine the exact chronology of events and to know the moment the killing began.

The exact chronology of their landing in Crete is uncertain.

However, the exact typological chronology of this culture is still unclear.

The exact chronology of the later years of their rule are uncertain.

Together their reigns cover the years 681-700 but the exact chronology is unknown.