TY  - BOOK
A2  - Burke Johnson, Larry Christensen.
A3  - Christensen, Larry B.
AU  - Johnson, R. Burke.
ET  - 4th ed.
NV  - XXVI, 621 s. :
PY  - 2012
SN  - 9781412978286
TI  - Educational research : quantitative, qualitative, and mixed approaches /
ER  -