Simultaneous approximation and global smoothness preservation
C. Cottin, H.H. Gonska, in: Circolo Matematico di Palermo (Ed.), Proceedings of the Second International Conference in Functional Analysis and Approximation Theory, 1993.

Directional extensions of univariate operators and Boolean sum approximation
C. Cottin, Analysis 13 (1993) 185–200.

Directional K- Functionals
C. Cottin, Results in Mathematics 24 (1993) 211–221.

A note on global smoothness preservation by Boolean sum operators
C. Cottin, H.H. Gonska, in: K.G. Ivanov, P.P. Petrushev, B.H. Sendov, V.A. Popov, Publ. House of the Bulgarian Academy of Sciences (Eds.), Constructive Theory of Functions, Proc. Conf. Varna 1991, Sofia, 1992, pp. 85–91.

A Jackson-type theorem on approximation by bounded trigonometric blending polynomials
C. Cottin, in: K.G. Ivanov, P.P. Petrushev, B.H. Sendov, V.A. Popov, Publ. House of the Bulgarian Academy of Sciences (Eds.), Constructive Theory of Functions, Proc. Conf. Varna 1991, Sofia, 1992, pp. 77–83.

Korovkin-type theorems for generalized Boolean sum operators
C. Badea, C. Cottin, in: Societatis Janos Bolyai  (Ed.), Proc. Conf. “Approximation Theory” Kecskemét 1990, Colloquia Mathematica Societatis Janos Bolyai 58, 1992, pp. 51–68.

Hierarchien: Status und Entlohnung/On the Pareto-Efficiency of Profit-Sharing-Contracts
V. Carstensen, Jahrbücher Für Nationalökonomie Und Statistik 210 (1992) 445–456.

‘Neue Selbständige’ in Ostdeutschland. Statusentscheidung, Realisierungschancen und materielle Zufriedenheit
M. Pannenberg, F. Büchel, Mitteilungen Aus Der Arbeitsmarkt- Und Berufsforschung 25 (1992) 544–552.

Erwerbsbiographische Folgerisiken von Kurzarbeit und Arbeitslosigkeit. Eine empirische Analyse für Ostdeutschland
M. Pannenberg, F. Büchel, Mitteilungen Aus Der Arbeitsmarkt- Und Berufsforschung 25 (1992) 158–167.

Finite Difference Schemes on Triangular Cell-Centered Grids with Local Refinement
P.S. Vassilevski, S. Petrova, R.D. Lazarov, SIAM Journal on Scientific and Statistical Computing 13 (1992) 1287–1313.

Approximation by bounded pseudo-polynomials
C. Cottin, in: Function Spaces, Proc. Conf. Poznan 1989, Teubner, 1991, pp. 152–161.

Global smoothness preservation by multivariate approximation operators
C. Anastassiou, C. Cottin, H. Gonska, in: S. Baron, D. Leviatan (Eds.), Israel Mathematical Conference Proceedings, Vol. IV, 1991, pp. 31–44.

Global smoothness of approximating functions
G.A. Anastassiou, C. Cottin, H.H. Gonska, Analysis 11 (1991).

3D reconstruction of closed objects by piecewise cubic Bézier patches
C. Cottin, R. van Damme, in: D.C. Handscomb (Ed.), The Mathematics of Surfaces III, Proc. Conf. Bath 1990, Oxford University Press, 1990.

Mixed K-functionals: A measure of smoothness for blending-type approximation
C. Cottin, Mathematische Zeitschrift 204 (1990) 69–83.

Inverse theorems for blending-type approximation
C. Cottin, in: C.K. Chui, L.L. Schumaker, J.D. Ward (Eds.), Approximation Theory VI, Proc. Conf. College Station (Texas), Academic Press, 1989, pp. 149–152.

A Korovkin-type theorem for generalizations of Boolean sum operators and approximation by trigonometric pseudopolynomials
C. Badea, I.A. Badea, C. Cottin, Revue d’Analyse Numérique et de La Théorie de l’Approximation 17 (1988) 7–17.

Quantitative Aussagen zur Blending-Typ-Approximation
C. Cottin, Quantitative Aussagen zur Blending-Typ-Approximation, 1988.

Notes on degree of approximation of B-continuous and B-differentiable functions.
C. Badea, I. Badea, C. Cottin, H.H. Gonska, Journal of Approximation Theory and Its Applications 4 (1988) 95–108.

A note on construction of preconditioners in solving 3D elliptic problems by substructuring
P.S. Vassilevski, S. Petrova, Comptes Rendus de l’Academie Bulgare Des Sciences 41 (1988) 33–36.