The polymer induced alignment (PIA) technique is presented as a new technique to grow single-crystalline films of linear telomers. Combining the PIA technique with special high-resolution Brillouin techniques, it is possible to determine the coefficients of the elastic stiffness tensor of the crystalline state of linear telomers. Especially in their rotator phases. As model systems we have chosen the perfluoroalkane C₂₀F₄₂ and the linear n-alkane C₁₇H₃₆. A comparison of elastic data obtained from classically and PIA grown samples proves their equivalence as well as their complementarity. Precursors of critical melting discovered in the rotator phase of C₁₇H₃₆. are discussed in terms of the anomalous temperature dependence of certain elastic tensor coefficients and of related n-telomers.