Retraction notice to “Efficient preparation of biodiesel from rapeseed oil over modified CaO” (Applied Energy (2011) 88(8) (2735–2739), (S0306261911001322) (10.1016/j.apenergy.2011.02.033))

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of Editor-in-Chief. The article is a duplicate of a paper that has already been published in Bull. Chem. Soc. Ethiop. 2011, 25(1), 37-42 (http://www.ajol.info/index.php/bcse/article/viewFile/63359/51224). One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper is not under consideration for publication elsewhere. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.