麻烦帮忙查找一下这4篇文献，非常感谢！最近在写开题报告，需要的文献较多，请谅解。

【序号】：1
【作者】：Saskia Thurnhofer
【题名】：Application of Ethyl Esters and d3-Methyl Esters as Internal Standards for the Gas Chromatographic Quantification of Transesterified Fatty Acid Methyl Esters in Food
【期刊】： J. Agric. Food Chem.
【年、卷、期、起止页码】： 2006, 54 (9), pp 3209–3214
【全文链接】：http://pubs.acs.org/doi/abs/10.1021/jf053022j

【序号】：2
【作者】：Andreas Barnsteiner?, Tim Lubinus?, Angelica di Gianvito?, Wolfgang Schmid?, and Karl-Heinz Engel*?
【题名】：GC-Based Analysis of Plant Stanyl Fatty Acid Esters in Enriched Foods
【期刊】： J. Agric. Food Chem.
【年、卷、期、起止页码】：  2011, 59 (10), pp 5204–5214
【全文链接】：http://pubs.acs.org/doi/abs/10.1021/jf104930z

【序号】：3
【作者】：Leila Hejazi??, Diako Ebrahimi*?, Michael Guilhaus? and D. Brynn Hibbert
【题名】：Determination of the Composition of Fatty Acid Mixtures Using GC × FI-MS: A Comprehensive Two-Dimensional Separation Approach
【期刊】： Anal. Chem.
【年、卷、期、起止页码】：2009, 81 (4), pp 1450–1458
【全文链接】：http://pubs.acs.org/doi/abs/10.1021/ac802277c

【序号】：4
【作者】：Michael J. Haas*?, Nadia Adawi§, William W. Berry#, Elaine Feldman§, Stephen Kasprzyk§, Brian Ratigan§, Karen Scott? and Emily Bockian Landsburg
【题名】：Butter as a Feedstock for Biodiesel Production
【期刊】： J. Agric. Food Chem.
【年、卷、期、起止页码】：2010, 58 (13), pp 7680–7684
【全文链接】：http://pubs.acs.org/doi/abs/10.1021/jf1003754