Analisis yuridis terhadap persekongkolan tender dan penerapan pembuktian tidak langsung (indirect evidence) : studi kasus terhadap putusan Komisi Pengawas Persaingan Usaha dan Badan Peradilan di Indonesia = Juridical analysis in terms of both tender conspiracy and application of indirect evidence : case study on award of business competition commission supervisory and judicature institution in Indonesia / Ibnu Abas Ali