Media type: E-Article Title: Higher-order gravitational couplings and modular forms in N = 2, D = 4 heterotic string compactifications Contributor: de Wit, Bernard; Lopes Cardoso, Gabriel; Lüst, Dieter; Mohaupt, Thomas; Rey, Soo-Jong imprint: Elsevier BV, 1996 Published in: Nuclear Physics B Language: English DOI: 10.1016/s0550-3213(96)90141-8 ISSN: 0550-3213 Keywords: Nuclear and High Energy Physics Origination: Footnote: