Vandeberg, L., Murre, J. M. J., Voorveld, H. A. M., & Smit, E. G. (2015). Dissociating explicit and implicit effects of cross-media advertising. International Journal of Advertising, 34(5), 744-764. doi:10.1080/02650487.2015.1011023.

Abstract:
Knowledge of cross-media advertising effects is mainly based on explicit psychological measures, such as self-reports. To fully understand the mechanisms responsible for the success of cross-media advertising, it is important to also use implicit measures. We used both types of measures to assess whether exposure to different media combinations affects the cognitive and evaluative impact of advertising. Results show that participants performed better on all explicit and implicit measures of memory and brand preference after exposure (versus no exposure) to target ads, which validated the use of these measures. Comparison of cross-media versus single medium exposure showed differences on the explicit level, but not on the implicit level. This suggests (1) that cross-media advantages may be driven by explicit rather than implicit memory mechanisms, and (2) that implicit advertising effects may require more drastic manipulations than context changes, such as varying the combination of media used for exposure to advertising.

Link: http://www.tandfonline.com/doi/abs/10.1080/