Secondary referencing is where you need to refer to the work of an author which you have not read in the original, but have learnt about from another author. Whenever possible you should use the original work. If this is not feasible, you must make clear that you have not read the original by referring to the work in which you found the reference.
Gibbs 'reflective cycle (1988) cited in Jasper (2013) shows that...
Gibbs’ reflective cycle is a seminal theory in reflective practice (Gibbs, 1988, cited in Jasper, 2013).
In the reference list only include details of the work that you read.
Jasper, M. (2013). Beginning reflective practice (2nd ed.). Andover: Cengage Learning.