The phrase "and therefore a third" is correct and usable in written English.
It can be used to indicate that something is being added or included as a third element or point in a discussion or argument.
Example: "We have two options on the table, and therefore a third could be proposed if we consider alternative solutions."
Alternatives: "and thus a third" or "and consequently a third".
Demographic isolation is a quasi-dependent variable and therefore a second model was developed using surrogate variables for demographic isolation.
They proved as much seven days ago, when Milner-Skudder bamboozled half the French team with a single step off his right foot, while Savea strong-armed his way to a hat-trick – his second of the tournament and therefore a first.
Remember, the skin is the largest organ for detoxification and therefore a first line of defense for your body.
He said that, though he had grown up in Pakistan, the Pakistanis looked upon him as an Indian, "and therefore a second-class citizen.
During Æthelbald's youth, Penda's dynasty ruled Mercia; Ceolred, a grandson of Penda and therefore a second cousin of Æthelbald, was king of Mercia from 709 to 716.
These simulations thus also afforded simple assessments of the sizes of the respective basins of attraction to either the zero- or endemic equilibrium points, and therefore a first examination of the resilience, i.e. the magnitude of perturbations a system can withstand before it changes stable states, [19] [21], of each system to either stable state.
This is however very subjective, and therefore a second observer also performed this analysis in order to measure observer agreement.
In this strain, it can be expected that maltose is very quickly converted extracellularly to d-glucose by the overproduction of glucoamylase, and therefore a second growth experiment was performed at different d-glucose concentrations to determine whether this morphology was indeed caused by the d-glucose level.
