We combine the theory of inside-source/inside-detector x-ray fluorescence holography and Kossel lines/x ray standing waves in kinematic approximation to directly obtain the phases of the diffraction structure factors. The influence of Kossel lines and standing waves on holography is also discussed. We obtain partial phase determination from experimental data obtaining the sign of the real part of the structure factor for several reciprocal lattice vectors of a vanadium crystal.PACS numbers: 61.10.-i, 07.85.-m, 42.20.-i The phase determination of diffracted beams is the central problem of x-ray crystallography. Several methods exist to obtain this information, such as direct methods [1], 3-beam diffraction [2], anomalous diffraction, heavy atom or molecular replacement [3] and x-ray standing waves or Kossel lines [4,5,6]. Despite the many advances in these methods, not all problems can be solved. Direct methods fail when the unit cell contains a large number of atoms. Anomalous diffraction and related methods are among the most successful methods for biological crystallography, but they often require chemical modification of the molecules. Multiple beam diffraction, x-ray standing waves and Kossel lines have usually been applied only to high-quality crystals of relatively simple structures, or to the localization of dopants in high quality crystals [7].Kossel lines are formed when a source of short wavelength radiation (∼ 1Å) is located on a crystallographic site: they result from the Bragg scattering of outgoing fluorescent x-rays from various sets of planes in the lattice. In the notation of holography, this is an "insidesource" experiment. The fine structure of these lines has been explained by the dynamical theory of x-ray diffraction via the reciprocity theorem used in optics [4]. A proper analysis of the KL fine structure allows the determination of the phases of reflections [5,6,8,10,11]. In parallel to this work on KL, the x-ray standing wave (XSW) method has been developed [5,6,7,10]. In this case, the source and the detector are interchanged as compared to the KL method: the atoms are subject to the changing wave-field in the crystal as the incident beam goes through a Bragg reflection, and fluorescent radiation proportional to the field at the atom is generated. This constitutes the "inside-detector" configuration in holography [8]. Besides the fine structure of the KL or XSW produced when the crystal orientation satisfies a Bragg or Laue condition, tails are formed far from the Bragg angle. These coarse features, also formed by poorer-quality mosaic crystals provide information on the real and imaginary part of the structure factor [10,11].Unlike standard imaging methods, holography offers the possibility of extracting both intensity and phase information. X-ray fluorescence holography (XFH) is thus a very promising new method for obtaining a direct image in real space of the local environments of different atomic species in reasonably well-ordered crystals or molecular ensembles. Long-range transl...