The phrase "a time span of three" is correct and usable in written English.
It can be used when referring to a duration or interval that lasts for three units of time, such as days, months, or years.
Example: "The project is expected to take a time span of three months to complete."
Alternatives: "a duration of three" or "a period of three".
Manager D, with a time span of two to three years, did not feel that C, with a time span of three to four, was distant enough hierarchically to take orders from.
Here, we present our results on quantitative analysis of a wide range of invertebrates over a time span of three years to characterize their association with Caenorhabditis species.
First, it covers a time span of three decades allowing the depiction of long term trends for the number of new and total registered physicians and for physician density.
Polymers were designed to release 1000 ng adenosine per day during a time span of ten days.
Within this organizational framework the Loss Prevention Symposium series, organized throughout Europe on behalf of the Loss Prevention Working Party of the EFCE, represents a fruitful tradition covering a time span of forty years.
Drawing data from 28 states of India over a time span of five years (2005 2009), this paper examines the role played by socio-economic and governance factors in determining the extent of electricity thefts in Indian states.
Echostar-2's spin axis was observed to have moved approximately 180° in right ascension, within a time span of six months, suggesting a roughly one year spin axis precession period about the satellite's angular momentum vector.
However, for observation purposes, a time span of five transaction days, which is equivalent to approximately one week, was selected.
Under these assumptions, sentence (19) says that Pollini played Opus 111 repeatedly within a time span of two weeks.
The 1984 Canadian study used an accounting ledger for 44 patients at one center during a time span of one year.
The dataset has been provided by Telecom Italia in the context of the 'Telecom Big Data Challenge' [30] and contains the mobile phone activity records - including both SMS and calls made or received - of all users in the Milan area (Italy) during a time span of two months, from November 1 to December 31, 2013.
