diff --git a/diffeomorphic_approx_3d_lp_le2_v2.txt b/diffeomorphic_approx_3d_lp_le2_v2.txt
index 3a37ddc..5605a24 100644
--- a/diffeomorphic_approx_3d_lp_le2_v2.txt
+++ b/diffeomorphic_approx_3d_lp_le2_v2.txt
@@ -59,7 +59,7 @@ there to Craig Evans), one starts with a Sobolev homeomorphism and
 asks whether diffeomorphisms onto the same target can approach it in
 the Sobolev norm.
 
-./ball-2001-singularities-computation-minimizers.pdf
+./pdf/ball-2001-singularities-computation-minimizers.pdf
 
 In the plane, Iwaniec, Kovalev and Onninen proved strong approximation
 for 1 < p < infinity, Hencl and Pratelli added the endpoint p = 1, and
@@ -89,17 +89,17 @@ recent survey records progress and open problems in the Ball-Evans
 question, following Ball's own account of the nonlinear-elasticity
 motivations.
 
-./iwaniec-kovalev-onninen-2011-diffeomorphic-approx.pdf
-./iwaniec-kovalev-onninen-2012-hopf-differentials.pdf
-./daneri-pratelli-2011-bi-lipschitz-approx.pdf
-./campbell-hencl-tengvall-2018-jacobian-signs.pdf
-./hencl-maly-2010-jacobians-sobolev-homeos.pdf
-./vaisala-1977-pl-approximation-lipeomorphisms.pdf
-./mora-corral-pratelli-2014-pam-approx.pdf
-./campbell-soudsky-2021-smooth-homeomorphic-approx.pdf
-./campbell-donofrio-vitek-2026-diffeomorphic-approx-pam.pdf
-./hencl-2025-survey-sobolev-homeos.pdf
-./ball-2010-progress-puzzles-nonlinear-elasticity.pdf
+./pdf/iwaniec-kovalev-onninen-2011-diffeomorphic-approx.pdf
+./pdf/iwaniec-kovalev-onninen-2012-hopf-differentials.pdf
+./pdf/daneri-pratelli-2011-bi-lipschitz-approx.pdf
+./pdf/campbell-hencl-tengvall-2018-jacobian-signs.pdf
+./pdf/hencl-maly-2010-jacobians-sobolev-homeos.pdf
+./pdf/vaisala-1977-pl-approximation-lipeomorphisms.pdf
+./pdf/mora-corral-pratelli-2014-pam-approx.pdf
+./pdf/campbell-soudsky-2021-smooth-homeomorphic-approx.pdf
+./pdf/campbell-donofrio-vitek-2026-diffeomorphic-approx-pam.pdf
+./pdf/hencl-2025-survey-sobolev-homeos.pdf
+./pdf/ball-2010-progress-puzzles-nonlinear-elasticity.pdf
 
 Throughout, a domain is a nonempty connected open set. All domains,
 closures, and compactness statements are relative to the ambient open
@@ -202,10 +202,10 @@ derivative estimates. The classical inputs are:
         Hatcher 2002: the Brouwer degree and the van Kampen theorem,
         as classically presented.
 
-./hamilton-1976-triangulation-3-manifolds.pdf
-./papakyriakopoulos-1957-dehns-lemma-asphericity-knots.pdf
-./li-watts-2011-s2-diffeos-so3.pdf
-./hatcher-2002-algebraic-topology.pdf
+./pdf/hamilton-1976-triangulation-3-manifolds.pdf
+./pdf/papakyriakopoulos-1957-dehns-lemma-asphericity-knots.pdf
+./pdf/li-watts-2011-s2-diffeos-so3.pdf
+./pdf/hatcher-2002-algebraic-topology.pdf
 
 These supply EXISTENCE of a homeomorphic replacement. They do not
 estimate its derivative: a PL approximant might have arbitrarily large
@@ -1384,7 +1384,7 @@ the disk estimate uses Ahlfors-Bers' measurable Riemann mapping theorem
 to conformally straighten a metric on the source square; the cell
 collapse uses the integrability of r^{m-1-p} when p < m.
 
-./ahlfors-bers-1960-riemann-mapping-variable-metrics.pdf
+./pdf/ahlfors-bers-1960-riemann-mapping-variable-metrics.pdf
 
 Definitions. Let Q = [-1/2, 1/2]^2. For a bi-Lipschitz embedding h : Q
 -> R^d, put
@@ -2026,8 +2026,8 @@ Properties (c) and (d) follow by generic-position arguments: the set
 of translations that miss them has measure zero, by countable
 intersection over the locally finite family and the stratification. QED
 
-./csornyei-hencl-maly-2010-homeos-sobolev-wnminus1.pdf
-./bojarski-hajlasz-1993-pointwise-sobolev.pdf
+./pdf/csornyei-hencl-maly-2010-homeos-sobolev-wnminus1.pdf
+./pdf/bojarski-hajlasz-1993-pointwise-sobolev.pdf
 
 The next lemma produces the target meshes used later.
 Their shape does not need to be uniform; only bounded local site counts
@@ -2696,7 +2696,7 @@ continuous because F^{-1} is continuous. Consequently both systems
 have relative conical differentiability at a, and the length of an
 initial ray interval is its radius times 1 + o(1).
 
-./simon-2014-introduction-gmt.pdf
+./pdf/simon-2014-introduction-gmt.pdf
 
 Radial construction inside a retained block. On a retained candidate
 block Q, set up cubical polar coordinates aligned with a. The target